Remove sampling (#17)

dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/instrumentation/api/Tags.java

@@ -16,7 +16,6 @@ public class Tags {
   public static final String PEER_SERVICE = "peer.service";
   public static final String PEER_HOSTNAME = "peer.hostname";
   public static final String PEER_PORT = "peer.port";
-  public static final String SAMPLING_PRIORITY = "sampling.priority";
   public static final String SPAN_KIND = "span.kind";
   public static final String COMPONENT = "component";
   public static final String ERROR = "error";

dd-java-agent/agent-tooling/agent-tooling.gradle

@@ -1,6 +1,7 @@
 apply from: "${rootDir}/gradle/java.gradle"
 
 minimumBranchCoverage = 0.6
+minimumInstructionCoverage = 0.8
 excludedClassesCoverage += ['datadog.trace.agent.tooling.*']
 
 configurations {

dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/decorator/BaseDecorator.java

@@ -1,6 +1,5 @@
 package datadog.trace.agent.decorator;
 
-import datadog.trace.api.Config;
 import datadog.trace.api.DDTags;
 import datadog.trace.instrumentation.api.AgentScope;
 import datadog.trace.instrumentation.api.AgentSpan;
@@ -10,24 +9,11 @@ import java.net.Inet4Address;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
-import java.util.Arrays;
-import java.util.TreeSet;
 import java.util.concurrent.ExecutionException;
 
 public abstract class BaseDecorator {
 
-  protected final boolean traceAnalyticsEnabled;
+  protected BaseDecorator() {}
-  protected final float traceAnalyticsSampleRate;
-
-  protected BaseDecorator() {
-    final Config config = Config.get();
-    final String[] instrumentationNames = instrumentationNames();
-    traceAnalyticsEnabled =
-        instrumentationNames.length > 0
-            && config.isTraceAnalyticsIntegrationEnabled(
-                new TreeSet<>(Arrays.asList(instrumentationNames)), traceAnalyticsDefault());
-    traceAnalyticsSampleRate = config.getInstrumentationAnalyticsSampleRate(instrumentationNames);
-  }
 
   protected abstract String[] instrumentationNames();
 
@@ -35,19 +21,12 @@ public abstract class BaseDecorator {
 
   protected abstract String component();
 
-  protected boolean traceAnalyticsDefault() {
-    return false;
-  }
-
   public AgentSpan afterStart(final AgentSpan span) {
     assert span != null;
     if (spanType() != null) {
       span.setTag(DDTags.SPAN_TYPE, spanType());
     }
     span.setTag(Tags.COMPONENT.getKey(), component());
-    if (traceAnalyticsEnabled) {
-      span.setTag(DDTags.ANALYTICS_SAMPLE_RATE, traceAnalyticsSampleRate);
-    }
     return span;
   }
 

dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/decorator/HttpServerDecorator.java

@@ -36,11 +36,6 @@ public abstract class HttpServerDecorator<REQUEST, CONNECTION, RESPONSE> extends
     return DDSpanTypes.HTTP_SERVER;
   }
 
-  @Override
-  protected boolean traceAnalyticsDefault() {
-    return Config.get().isTraceAnalyticsEnabled();
-  }
-
   public AgentSpan onRequest(final AgentSpan span, final REQUEST request) {
     assert span != null;
     if (request != null) {

dd-java-agent/agent-tooling/src/test/groovy/datadog/trace/agent/decorator/BaseDecoratorTest.groovy

@@ -1,6 +1,6 @@
 package datadog.trace.agent.decorator
 
-import datadog.trace.agent.test.utils.ConfigUtils
+
 import datadog.trace.api.DDTags
 import datadog.trace.instrumentation.api.AgentScope
 import datadog.trace.instrumentation.api.AgentSpan
@@ -139,51 +139,6 @@ class BaseDecoratorTest extends DDSpecification {
     1 * scope.span() >> span
   }
 
-  def "test analytics rate default disabled"() {
-    when:
-    BaseDecorator dec = newDecorator(defaultEnabled, hasConfigNames)
-
-    then:
-    dec.traceAnalyticsEnabled == defaultEnabled
-    dec.traceAnalyticsSampleRate == sampleRate.floatValue()
-
-    where:
-    defaultEnabled | hasConfigNames | sampleRate
-    true           | false          | 1.0
-    false          | false          | 1.0
-    false          | true           | 1.0
-  }
-
-  def "test analytics rate enabled:#enabled, integration:#integName, sampleRate:#sampleRate"() {
-    setup:
-    ConfigUtils.updateConfig {
-      System.properties.setProperty("dd.${integName}.analytics.enabled", "true")
-      System.properties.setProperty("dd.${integName}.analytics.sample-rate", "$sampleRate")
-    }
-
-    when:
-    BaseDecorator dec = newDecorator(enabled)
-
-    then:
-    dec.traceAnalyticsEnabled == expectedEnabled
-    dec.traceAnalyticsSampleRate == (Float) expectedRate
-
-    cleanup:
-    System.clearProperty("dd.${integName}.analytics.enabled")
-    System.clearProperty("dd.${integName}.analytics.sample-rate")
-
-    where:
-    enabled | integName | sampleRate | expectedEnabled | expectedRate
-    false   | ""        | ""         | false           | 1.0
-    true    | ""        | ""         | true            | 1.0
-    false   | "test1"   | 0.5        | true            | 0.5
-    false   | "test2"   | 0.75       | true            | 0.75
-    true    | "test1"   | 0.2        | true            | 0.2
-    true    | "test2"   | 0.4        | true            | 0.4
-    true    | "test1"   | ""         | true            | 1.0
-    true    | "test2"   | ""         | true            | 1.0
-  }
-
   def "test spanNameForMethod"() {
     when:
     def result = decorator.spanNameForMethod(method)
@@ -201,68 +156,22 @@ class BaseDecoratorTest extends DDSpecification {
   }
 
   def newDecorator() {
-    return newDecorator(false)
+    return new BaseDecorator() {
-  }
+      @Override
+      protected String[] instrumentationNames() {
+        return []
+      }
 
-  def newDecorator(boolean analyticsEnabledDefault, boolean emptyInstrumentationNames = false) {
+      @Override
-    return emptyInstrumentationNames ?
+      protected String spanType() {
-      new BaseDecorator() {
+        return "test-type"
-        @Override
+      }
-        protected String[] instrumentationNames() {
-          return []
-        }
 
-        @Override
+      @Override
-        protected String spanType() {
+      protected String component() {
-          return "test-type"
+        return "test-component"
-        }
+      }
-
+    }
-        @Override
-        protected String component() {
-          return "test-component"
-        }
-
-        protected boolean traceAnalyticsDefault() {
-          return true
-        }
-      } :
-      analyticsEnabledDefault ?
-        new BaseDecorator() {
-          @Override
-          protected String[] instrumentationNames() {
-            return ["test1", "test2"]
-          }
-
-          @Override
-          protected String spanType() {
-            return "test-type"
-          }
-
-          @Override
-          protected String component() {
-            return "test-component"
-          }
-
-          protected boolean traceAnalyticsDefault() {
-            return true
-          }
-        } :
-        new BaseDecorator() {
-          @Override
-          protected String[] instrumentationNames() {
-            return ["test1", "test2"]
-          }
-
-          @Override
-          protected String spanType() {
-            return "test-type"
-          }
-
-          @Override
-          protected String component() {
-            return "test-component"
-          }
-        }
   }
 
   class SomeInnerClass implements Runnable {

dd-java-agent/agent-tooling/src/test/groovy/datadog/trace/agent/decorator/ClientDecoratorTest.groovy

@@ -22,7 +22,6 @@ class ClientDecoratorTest extends BaseDecoratorTest {
     1 * span.setTag(Tags.COMPONENT.key, "test-component")
     1 * span.setTag(Tags.SPAN_KIND.key, "client")
     1 * span.setTag(DDTags.SPAN_TYPE, decorator.spanType())
-    1 * span.setTag(DDTags.ANALYTICS_SAMPLE_RATE, 1.0)
     _ * span.setTag(_, _) // Want to allow other calls from child implementations.
     0 * _
 
@@ -64,10 +63,6 @@ class ClientDecoratorTest extends BaseDecoratorTest {
       protected String component() {
         return "test-component"
       }
-
-      protected boolean traceAnalyticsDefault() {
-        return true
-      }
     }
   }
 }

dd-java-agent/agent-tooling/src/test/groovy/datadog/trace/agent/decorator/DatabaseClientDecoratorTest.groovy

@@ -26,7 +26,6 @@ class DatabaseClientDecoratorTest extends ClientDecoratorTest {
     1 * span.setTag(Tags.SPAN_KIND.key, "client")
     1 * span.setTag(Tags.DB_TYPE.key, "test-db")
     1 * span.setTag(DDTags.SPAN_TYPE, "test-type")
-    1 * span.setTag(DDTags.ANALYTICS_SAMPLE_RATE, 1.0)
     0 * _
 
     where:
@@ -138,10 +137,6 @@ class DatabaseClientDecoratorTest extends ClientDecoratorTest {
       protected String dbInstance(Map map) {
         return map.instance
       }
-
-      protected boolean traceAnalyticsDefault() {
-        return true
-      }
     }
   }
 }

dd-java-agent/agent-tooling/src/test/groovy/datadog/trace/agent/decorator/HttpClientDecoratorTest.groovy

@@ -174,10 +174,6 @@ class HttpClientDecoratorTest extends ClientDecoratorTest {
       protected Integer status(Map m) {
         return m.status
       }
-
-      protected boolean traceAnalyticsDefault() {
-        return true
-      }
     }
   }
 }

dd-java-agent/agent-tooling/src/test/groovy/datadog/trace/agent/decorator/ServerDecoratorTest.groovy

@@ -19,9 +19,6 @@ class ServerDecoratorTest extends BaseDecoratorTest {
     1 * span.setTag(Tags.COMPONENT.key, "test-component")
     1 * span.setTag(Tags.SPAN_KIND.key, "server")
     1 * span.setTag(DDTags.SPAN_TYPE, decorator.spanType())
-    if (decorator.traceAnalyticsEnabled) {
-      1 * span.setTag(DDTags.ANALYTICS_SAMPLE_RATE, 1.0)
-    }
     0 * _
   }
 
@@ -50,10 +47,6 @@ class ServerDecoratorTest extends BaseDecoratorTest {
       protected String component() {
         return "test-component"
       }
-
-      protected boolean traceAnalyticsDefault() {
-        return true
-      }
     }
   }
 }

dd-java-agent/instrumentation/ratpack-1.4/src/main/java8/datadog/trace/instrumentation/ratpack/RatpackServerDecorator.java

@@ -26,11 +26,6 @@ public class RatpackServerDecorator extends HttpServerDecorator<Request, Request
     return "ratpack";
   }
 
-  @Override
-  protected boolean traceAnalyticsDefault() {
-    return false;
-  }
-
   @Override
   protected String method(final Request request) {
     return request.getMethod().getName();

dd-java-agent/instrumentation/spring-webmvc-3.1/src/main/java/datadog/trace/instrumentation/springweb/SpringWebHttpServerDecorator.java

@@ -38,11 +38,6 @@ public class SpringWebHttpServerDecorator
     return "spring-web-controller";
   }
 
-  @Override
-  protected boolean traceAnalyticsDefault() {
-    return false;
-  }
-
   @Override
   protected String method(final HttpServletRequest httpServletRequest) {
     return httpServletRequest.getMethod();

dd-java-agent/testing/src/test/groovy/context/FieldBackedProviderTest.groovy

@@ -215,7 +215,6 @@ class FieldBackedProviderFieldInjectionDisabledTest extends AgentTestRunner {
     }
 
     expect:
-    Config.get().isPrioritySamplingEnabled() == false
     hasField == false
     hasMarkerInterface == false
     hasAccessorInterface == false

dd-trace-api/src/main/java/datadog/trace/api/Config.java

@@ -51,13 +51,11 @@ public class Config {
   public static final String TRACE_AGENT_PORT = "trace.agent.port";
   public static final String AGENT_PORT_LEGACY = "agent.port";
   public static final String AGENT_UNIX_DOMAIN_SOCKET = "trace.agent.unix.domain.socket";
-  public static final String PRIORITY_SAMPLING = "priority.sampling";
   public static final String TRACE_RESOLVER_ENABLED = "trace.resolver.enabled";
   public static final String SERVICE_MAPPING = "service.mapping";
   public static final String GLOBAL_TAGS = "trace.global.tags";
   public static final String SPAN_TAGS = "trace.span.tags";
   public static final String JMX_TAGS = "trace.jmx.tags";
-  public static final String TRACE_ANALYTICS_ENABLED = "trace.analytics.enabled";
   public static final String TRACE_ANNOTATIONS = "trace.annotations";
   public static final String TRACE_EXECUTORS_ALL = "trace.executors.all";
   public static final String TRACE_EXECUTORS = "trace.executors";
@@ -104,7 +102,6 @@ public class Config {
 
   private static final boolean DEFAULT_RUNTIME_CONTEXT_FIELD_INJECTION = true;
 
-  private static final boolean DEFAULT_PRIORITY_SAMPLING_ENABLED = true;
   private static final boolean DEFAULT_TRACE_RESOLVER_ENABLED = true;
   private static final Set<Integer> DEFAULT_HTTP_SERVER_ERROR_STATUSES =
       parseIntegerRangeSet("500-599", "default");
@@ -131,8 +128,6 @@ public class Config {
   private static final boolean DEFAULT_TRACE_EXECUTORS_ALL = false;
   private static final String DEFAULT_TRACE_EXECUTORS = "";
   private static final String DEFAULT_TRACE_METHODS = null;
-  public static final boolean DEFAULT_TRACE_ANALYTICS_ENABLED = false;
-  public static final float DEFAULT_ANALYTICS_SAMPLE_RATE = 1.0f;
 
   public enum PropagationStyle {
     DATADOG,
@@ -156,7 +151,6 @@ public class Config {
   @Getter private final String agentHost;
   @Getter private final int agentPort;
   @Getter private final String agentUnixDomainSocket;
-  @Getter private final boolean prioritySamplingEnabled;
   @Getter private final boolean traceResolverEnabled;
   @Getter private final Map<String, String> serviceMapping;
   private final Map<String, String> globalTags;
@@ -191,8 +185,6 @@ public class Config {
   @Getter private final boolean traceExecutorsAll;
   @Getter private final List<String> traceExecutors;
 
-  @Getter private final boolean traceAnalyticsEnabled;
-
   // Values from an optionally provided properties file
   private static Properties propertiesFromConfigFile;
 
@@ -216,8 +208,6 @@ public class Config {
             getIntegerSettingFromEnvironment(AGENT_PORT_LEGACY, DEFAULT_TRACE_AGENT_PORT));
     agentUnixDomainSocket =
         getSettingFromEnvironment(AGENT_UNIX_DOMAIN_SOCKET, DEFAULT_AGENT_UNIX_DOMAIN_SOCKET);
-    prioritySamplingEnabled =
-        getBooleanSettingFromEnvironment(PRIORITY_SAMPLING, DEFAULT_PRIORITY_SAMPLING_ENABLED);
     traceResolverEnabled =
         getBooleanSettingFromEnvironment(TRACE_RESOLVER_ENABLED, DEFAULT_TRACE_RESOLVER_ENABLED);
     serviceMapping = getMapSettingFromEnvironment(SERVICE_MAPPING, null);
@@ -299,9 +289,6 @@ public class Config {
 
     traceExecutors = getListSettingFromEnvironment(TRACE_EXECUTORS, DEFAULT_TRACE_EXECUTORS);
 
-    traceAnalyticsEnabled =
-        getBooleanSettingFromEnvironment(TRACE_ANALYTICS_ENABLED, DEFAULT_TRACE_ANALYTICS_ENABLED);
-
     log.debug("New instance: {}", this);
   }
 
@@ -323,8 +310,6 @@ public class Config {
             getPropertyIntegerValue(properties, AGENT_PORT_LEGACY, parent.agentPort));
     agentUnixDomainSocket =
         properties.getProperty(AGENT_UNIX_DOMAIN_SOCKET, parent.agentUnixDomainSocket);
-    prioritySamplingEnabled =
-        getPropertyBooleanValue(properties, PRIORITY_SAMPLING, parent.prioritySamplingEnabled);
     traceResolverEnabled =
         getPropertyBooleanValue(properties, TRACE_RESOLVER_ENABLED, parent.traceResolverEnabled);
     serviceMapping = getPropertyMapValue(properties, SERVICE_MAPPING, parent.serviceMapping);
@@ -408,9 +393,6 @@ public class Config {
         getPropertyBooleanValue(properties, TRACE_EXECUTORS_ALL, parent.traceExecutorsAll);
     traceExecutors = getPropertyListValue(properties, TRACE_EXECUTORS, parent.traceExecutors);
 
-    traceAnalyticsEnabled =
-        getPropertyBooleanValue(properties, TRACE_ANALYTICS_ENABLED, parent.traceAnalyticsEnabled);
-
     log.debug("New instance: {}", this);
   }
 
@@ -453,20 +435,6 @@ public class Config {
     return Collections.unmodifiableMap(result);
   }
 
-  /**
-   * Returns the sample rate for the specified instrumentation or {@link
-   * #DEFAULT_ANALYTICS_SAMPLE_RATE} if none specified.
-   */
-  public float getInstrumentationAnalyticsSampleRate(final String... aliases) {
-    for (final String alias : aliases) {
-      final Float rate = getFloatSettingFromEnvironment(alias + ".analytics.sample-rate", null);
-      if (null != rate) {
-        return rate;
-      }
-    }
-    return DEFAULT_ANALYTICS_SAMPLE_RATE;
-  }
-
   /**
    * Return a map of tags required by the datadog backend to link runtime metrics (i.e. jmx) and
    * traces.
@@ -511,35 +479,6 @@ public class Config {
     return anyEnabled;
   }
 
-  public boolean isTraceAnalyticsIntegrationEnabled(
-      final SortedSet<String> integrationNames, final boolean defaultEnabled) {
-    return traceAnalyticsIntegrationEnabled(integrationNames, defaultEnabled);
-  }
-
-  /**
-   * @deprecated This method should only be used internally. Use the instance getter instead {@link
-   *     #isTraceAnalyticsIntegrationEnabled(SortedSet, boolean)}.
-   * @param integrationNames
-   * @param defaultEnabled
-   * @return
-   */
-  public static boolean traceAnalyticsIntegrationEnabled(
-      final SortedSet<String> integrationNames, final boolean defaultEnabled) {
-    // If default is enabled, we want to enable individually,
-    // if default is disabled, we want to disable individually.
-    boolean anyEnabled = defaultEnabled;
-    for (final String name : integrationNames) {
-      final boolean configEnabled =
-          getBooleanSettingFromEnvironment(name + ".analytics.enabled", defaultEnabled);
-      if (defaultEnabled) {
-        anyEnabled &= configEnabled;
-      } else {
-        anyEnabled |= configEnabled;
-      }
-    }
-    return anyEnabled;
-  }
-
   /**
    * Helper method that takes the name, adds a "dd." prefix then checks for System Properties of
    * that name. If none found, the name is converted to an Environment Variable and used to check

dd-trace-api/src/main/java/datadog/trace/api/DDTags.java

@@ -16,12 +16,4 @@ public class DDTags {
   public static final String ERROR_MSG = "error.msg"; // string representing the error message
   public static final String ERROR_TYPE = "error.type"; // string representing the type of the error
   public static final String ERROR_STACK = "error.stack"; // human readable version of the stack
-
-  public static final String ANALYTICS_SAMPLE_RATE = "_dd1.sr.eausr";
-  @Deprecated public static final String EVENT_SAMPLE_RATE = ANALYTICS_SAMPLE_RATE;
-
-  /** Manually force tracer to be keep the trace */
-  public static final String MANUAL_KEEP = "manual.keep";
-  /** Manually force tracer to be drop the trace */
-  public static final String MANUAL_DROP = "manual.drop";
 }

dd-trace-api/src/main/java/datadog/trace/api/interceptor/MutableSpan.java

@@ -22,18 +22,6 @@ public interface MutableSpan {
 
   MutableSpan setResourceName(final String resourceName);
 
-  Integer getSamplingPriority();
-
-  /**
-   * @deprecated Use {@link io.opentracing.Span#setTag(String, boolean)} instead using either tag
-   *     names {@link datadog.trace.api.DDTags#MANUAL_KEEP} or {@link
-   *     datadog.trace.api.DDTags#MANUAL_DROP}.
-   * @param newPriority
-   * @return
-   */
-  @Deprecated
-  MutableSpan setSamplingPriority(final int newPriority);
-
   String getSpanType();
 
   MutableSpan setSpanType(final String type);

dd-trace-api/src/main/java/datadog/trace/api/interceptor/TraceInterceptor.java

@@ -6,7 +6,7 @@ public interface TraceInterceptor {
 
   /**
    * After a trace is "complete" but before it is written, it is provided to the interceptors to
-   * modify. The result following all interceptors is sampled then sent to the trace writer.
+   * modify. The result following all interceptors is then sent to the trace writer.
    *
    * @param trace - The collection of spans that represent a trace. Can be modified in place. Order
    *     of spans should not be relied upon.

dd-trace-api/src/main/java/datadog/trace/api/sampling/PrioritySampling.java

@@ -1,20 +0,0 @@
-package datadog.trace.api.sampling;
-
-public class PrioritySampling {
-  /**
-   * Implementation detail of the client. will not be sent to the agent or propagated.
-   *
-   * <p>Internal value used when the priority sampling flag has not been set on the span context.
-   */
-  public static final int UNSET = Integer.MIN_VALUE;
-  /** The sampler has decided to drop the trace. */
-  public static final int SAMPLER_DROP = 0;
-  /** The sampler has decided to keep the trace. */
-  public static final int SAMPLER_KEEP = 1;
-  /** The user has decided to drop the trace. */
-  public static final int USER_DROP = -1;
-  /** The user has decided to keep the trace. */
-  public static final int USER_KEEP = 2;
-
-  private PrioritySampling() {}
-}

dd-trace-api/src/test/groovy/datadog/trace/api/ConfigTest.groovy

@@ -21,7 +21,6 @@ import static datadog.trace.api.Config.HTTP_SERVER_ERROR_STATUSES
 import static datadog.trace.api.Config.JMX_TAGS
 import static datadog.trace.api.Config.PARTIAL_FLUSH_MIN_SPANS
 import static datadog.trace.api.Config.PREFIX
-import static datadog.trace.api.Config.PRIORITY_SAMPLING
 import static datadog.trace.api.Config.PROPAGATION_STYLE_EXTRACT
 import static datadog.trace.api.Config.PROPAGATION_STYLE_INJECT
 import static datadog.trace.api.Config.RUNTIME_CONTEXT_FIELD_INJECTION
@@ -66,7 +65,6 @@ class ConfigTest extends DDSpecification {
     config.agentHost == "localhost"
     config.agentPort == 8126
     config.agentUnixDomainSocket == null
-    config.prioritySamplingEnabled == true
     config.traceResolverEnabled == true
     config.serviceMapping == [:]
     config.mergedSpanTags == [:]
@@ -105,7 +103,6 @@ class ConfigTest extends DDSpecification {
     prop.setProperty(TRACE_AGENT_PORT, "123")
     prop.setProperty(AGENT_UNIX_DOMAIN_SOCKET, "somepath")
     prop.setProperty(AGENT_PORT_LEGACY, "456")
-    prop.setProperty(PRIORITY_SAMPLING, "false")
     prop.setProperty(TRACE_RESOLVER_ENABLED, "false")
     prop.setProperty(SERVICE_MAPPING, "a:1")
     prop.setProperty(GLOBAL_TAGS, "b:2")
@@ -136,7 +133,6 @@ class ConfigTest extends DDSpecification {
     config.agentHost == "somehost"
     config.agentPort == 123
     config.agentUnixDomainSocket == "somepath"
-    config.prioritySamplingEnabled == false
     config.traceResolverEnabled == false
     config.serviceMapping == [a: "1"]
     config.mergedSpanTags == [b: "2", c: "3"]
@@ -166,7 +162,6 @@ class ConfigTest extends DDSpecification {
     System.setProperty(PREFIX + TRACE_AGENT_PORT, "123")
     System.setProperty(PREFIX + AGENT_UNIX_DOMAIN_SOCKET, "somepath")
     System.setProperty(PREFIX + AGENT_PORT_LEGACY, "456")
-    System.setProperty(PREFIX + PRIORITY_SAMPLING, "false")
     System.setProperty(PREFIX + TRACE_RESOLVER_ENABLED, "false")
     System.setProperty(PREFIX + SERVICE_MAPPING, "a:1")
     System.setProperty(PREFIX + GLOBAL_TAGS, "b:2")
@@ -197,7 +192,6 @@ class ConfigTest extends DDSpecification {
     config.agentHost == "somehost"
     config.agentPort == 123
     config.agentUnixDomainSocket == "somepath"
-    config.prioritySamplingEnabled == false
     config.traceResolverEnabled == false
     config.serviceMapping == [a: "1"]
     config.mergedSpanTags == [b: "2", c: "3"]
@@ -268,7 +262,6 @@ class ConfigTest extends DDSpecification {
     System.setProperty(PREFIX + AGENT_HOST, " ")
     System.setProperty(PREFIX + TRACE_AGENT_PORT, " ")
     System.setProperty(PREFIX + AGENT_PORT_LEGACY, "invalid")
-    System.setProperty(PREFIX + PRIORITY_SAMPLING, "3")
     System.setProperty(PREFIX + TRACE_RESOLVER_ENABLED, " ")
     System.setProperty(PREFIX + SERVICE_MAPPING, " ")
     System.setProperty(PREFIX + HEADER_TAGS, "1")
@@ -289,7 +282,6 @@ class ConfigTest extends DDSpecification {
     config.writerType == " "
     config.agentHost == " "
     config.agentPort == 8126
-    config.prioritySamplingEnabled == false
     config.traceResolverEnabled == true
     config.serviceMapping == [:]
     config.mergedSpanTags == [:]
@@ -354,7 +346,6 @@ class ConfigTest extends DDSpecification {
     properties.setProperty(AGENT_HOST, "somehost")
     properties.setProperty(TRACE_AGENT_PORT, "123")
     properties.setProperty(AGENT_UNIX_DOMAIN_SOCKET, "somepath")
-    properties.setProperty(PRIORITY_SAMPLING, "false")
     properties.setProperty(TRACE_RESOLVER_ENABLED, "false")
     properties.setProperty(SERVICE_MAPPING, "a:1")
     properties.setProperty(GLOBAL_TAGS, "b:2")
@@ -379,7 +370,6 @@ class ConfigTest extends DDSpecification {
     config.agentHost == "somehost"
     config.agentPort == 123
     config.agentUnixDomainSocket == "somepath"
-    config.prioritySamplingEnabled == false
     config.traceResolverEnabled == false
     config.serviceMapping == [a: "1"]
     config.mergedSpanTags == [b: "2", c: "3"]
@@ -463,40 +453,6 @@ class ConfigTest extends DDSpecification {
     integrationNames = new TreeSet<>(names)
   }
 
-  def "verify integration trace analytics config"() {
-    setup:
-    environmentVariables.set("DD_ORDER_ANALYTICS_ENABLED", "false")
-    environmentVariables.set("DD_TEST_ENV_ANALYTICS_ENABLED", "true")
-    environmentVariables.set("DD_DISABLED_ENV_ANALYTICS_ENABLED", "false")
-
-    System.setProperty("dd.order.analytics.enabled", "true")
-    System.setProperty("dd.test-prop.analytics.enabled", "true")
-    System.setProperty("dd.disabled-prop.analytics.enabled", "false")
-
-    expect:
-    Config.get().isTraceAnalyticsIntegrationEnabled(integrationNames, defaultEnabled) == expected
-
-    where:
-    names                          | defaultEnabled | expected
-    []                             | true           | true
-    []                             | false          | false
-    ["invalid"]                    | true           | true
-    ["invalid"]                    | false          | false
-    ["test-prop"]                  | false          | true
-    ["test-env"]                   | false          | true
-    ["disabled-prop"]              | true           | false
-    ["disabled-env"]               | true           | false
-    ["other", "test-prop"]         | false          | true
-    ["other", "test-env"]          | false          | true
-    ["order"]                      | false          | true
-    ["test-prop", "disabled-prop"] | false          | true
-    ["disabled-env", "test-env"]   | false          | true
-    ["test-prop", "disabled-prop"] | true           | false
-    ["disabled-env", "test-env"]   | true           | false
-
-    integrationNames = new TreeSet<>(names)
-  }
-
   def "test getFloatSettingFromEnvironment(#name)"() {
     setup:
     environmentVariables.set("DD_ENV_ZERO_TEST", "0.0")

dd-trace-ot/dd-trace-ot.gradle

@@ -8,11 +8,10 @@ apply from: "${rootDir}/gradle/java.gradle"
 apply from: "${rootDir}/gradle/publish.gradle"
 
 minimumBranchCoverage = 0.5
-minimumInstructionCoverage = 0.6
+minimumInstructionCoverage = 0.5
 excludedClassesCoverage += [
   'datadog.trace.common.writer.ListWriter',
   'datadog.trace.common.writer.LoggingWriter',
-  'datadog.trace.common.sampling.PrioritySampling',
   // This code is copied from okHttp samples and we have integration tests to verify that it works.
   'datadog.trace.common.writer.unixdomainsockets.TunnelingUnixSocket',
   'datadog.trace.common.writer.unixdomainsockets.UnixDomainSocketFactory'

dd-trace-ot/src/main/java/datadog/opentracing/DDSpan.java

@@ -6,7 +6,6 @@ import com.fasterxml.jackson.annotation.JsonGetter;
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import datadog.trace.api.DDTags;
 import datadog.trace.api.interceptor.MutableSpan;
-import datadog.trace.api.sampling.PrioritySampling;
 import datadog.trace.common.util.Clock;
 import io.opentracing.Span;
 import io.opentracing.tag.Tag;
@@ -276,17 +275,6 @@ public class DDSpan implements Span, MutableSpan {
     return this;
   }
 
-  /**
-   * Set the sampling priority of the root span of this span's trace
-   *
-   * <p>Has no effect if the span priority has been propagated (injected or extracted).
-   */
-  @Override
-  public final DDSpan setSamplingPriority(final int newPriority) {
-    context().setSamplingPriority(newPriority);
-    return this;
-  }
-
   @Override
   public final DDSpan setSpanType(final String type) {
     context().setSpanType(type);
@@ -367,17 +355,6 @@ public class DDSpan implements Span, MutableSpan {
     return context.getOperationName();
   }
 
-  @Override
-  @JsonIgnore
-  public Integer getSamplingPriority() {
-    final int samplingPriority = context.getSamplingPriority();
-    if (samplingPriority == PrioritySampling.UNSET) {
-      return null;
-    } else {
-      return samplingPriority;
-    }
-  }
-
   @Override
   @JsonIgnore
   public String getSpanType() {

dd-trace-ot/src/main/java/datadog/opentracing/DDSpanContext.java

@@ -3,7 +3,6 @@ package datadog.opentracing;
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import datadog.opentracing.decorators.AbstractDecorator;
 import datadog.trace.api.DDTags;
-import datadog.trace.api.sampling.PrioritySampling;
 import java.math.BigInteger;
 import java.util.Collections;
 import java.util.List;
@@ -23,8 +22,6 @@ import lombok.extern.slf4j.Slf4j;
  */
 @Slf4j
 public class DDSpanContext implements io.opentracing.SpanContext {
-  public static final String PRIORITY_SAMPLING_KEY = "_sampling_priority_v1";
-  public static final String SAMPLE_RATE_KEY = "_sample_rate";
   public static final String ORIGIN_KEY = "_dd.origin";
 
   private static final Map<String, Number> EMPTY_METRICS = Collections.emptyMap();
@@ -57,13 +54,6 @@ public class DDSpanContext implements io.opentracing.SpanContext {
   private volatile String spanType;
   /** True indicates that the span reports an error */
   private volatile boolean errorFlag;
-  /**
-   * When true, the samplingPriority cannot be changed. This prevents the sampling flag from
-   * changing after the context has propagated.
-   *
-   * <p>For thread safety, this boolean is only modified or accessed under instance lock.
-   */
-  private boolean samplingPriorityLocked = false;
   /** The origin of the trace. (eg. Synthetics) */
   private final String origin;
   /** Metrics on the span */
@@ -80,7 +70,6 @@ public class DDSpanContext implements io.opentracing.SpanContext {
       final String serviceName,
       final String operationName,
       final String resourceName,
-      final int samplingPriority,
       final String origin,
       final Map<String, String> baggageItems,
       final boolean errorFlag,
@@ -118,10 +107,6 @@ public class DDSpanContext implements io.opentracing.SpanContext {
     this.spanType = spanType;
     this.origin = origin;
 
-    if (samplingPriority != PrioritySampling.UNSET) {
-      setSamplingPriority(samplingPriority);
-    }
-
     if (origin != null) {
       this.tags.put(ORIGIN_KEY, origin);
     }
@@ -191,73 +176,6 @@ public class DDSpanContext implements io.opentracing.SpanContext {
     this.spanType = spanType;
   }
 
-  public void setSamplingPriority(final int newPriority) {
-    if (trace != null) {
-      final DDSpan rootSpan = trace.getRootSpan();
-      if (null != rootSpan && rootSpan.context() != this) {
-        rootSpan.context().setSamplingPriority(newPriority);
-        return;
-      }
-    }
-    if (newPriority == PrioritySampling.UNSET) {
-      log.debug("{}: Refusing to set samplingPriority to UNSET", this);
-      return;
-    }
-    // sync with lockSamplingPriority
-    synchronized (this) {
-      if (samplingPriorityLocked) {
-        log.debug(
-            "samplingPriority locked at {}. Refusing to set to {}",
-            getMetrics().get(PRIORITY_SAMPLING_KEY),
-            newPriority);
-      } else {
-        setMetric(PRIORITY_SAMPLING_KEY, newPriority);
-        log.debug("Set sampling priority to {}", getMetrics().get(PRIORITY_SAMPLING_KEY));
-      }
-    }
-  }
-
-  /** @return the sampling priority of this span's trace, or null if no priority has been set */
-  public int getSamplingPriority() {
-    if (trace != null) {
-      final DDSpan rootSpan = trace.getRootSpan();
-      if (null != rootSpan && rootSpan.context() != this) {
-        return rootSpan.context().getSamplingPriority();
-      }
-    }
-    final Number val = getMetrics().get(PRIORITY_SAMPLING_KEY);
-    return null == val ? PrioritySampling.UNSET : val.intValue();
-  }
-
-  /**
-   * Prevent future changes to the context's sampling priority.
-   *
-   * <p>Used when a span is extracted or injected for propagation.
-   *
-   * <p>Has no effect if the sampling priority is unset.
-   *
-   * @return true if the sampling priority was locked.
-   */
-  public boolean lockSamplingPriority() {
-    if (trace != null) {
-      final DDSpan rootSpan = trace.getRootSpan();
-      if (null != rootSpan && rootSpan.context() != this) {
-        return rootSpan.context().lockSamplingPriority();
-      }
-    }
-    // sync with setSamplingPriority
-    synchronized (this) {
-      if (getMetrics().get(PRIORITY_SAMPLING_KEY) == null) {
-        log.debug("{} : refusing to lock unset samplingPriority", this);
-      } else if (samplingPriorityLocked == false) {
-        samplingPriorityLocked = true;
-        log.debug(
-            "{} : locked samplingPriority to {}", this, getMetrics().get(PRIORITY_SAMPLING_KEY));
-      }
-      return samplingPriorityLocked;
-    }
-  }
-
   public String getOrigin() {
     final DDSpan rootSpan = trace.getRootSpan();
     if (null != rootSpan) {

dd-trace-ot/src/main/java/datadog/opentracing/DDTracer.java

@@ -10,11 +10,6 @@ import datadog.opentracing.scopemanager.ScopeContext;
 import datadog.trace.api.Config;
 import datadog.trace.api.interceptor.MutableSpan;
 import datadog.trace.api.interceptor.TraceInterceptor;
-import datadog.trace.api.sampling.PrioritySampling;
-import datadog.trace.common.sampling.RateByServiceSampler;
-import datadog.trace.common.sampling.Sampler;
-import datadog.trace.common.writer.DDAgentWriter;
-import datadog.trace.common.writer.DDApi;
 import datadog.trace.common.writer.Writer;
 import datadog.trace.context.ScopeListener;
 import io.opentracing.References;
@@ -58,8 +53,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
   final String serviceName;
   /** Writer is an charge of reporting traces and spans to the desired endpoint */
   final Writer writer;
-  /** Sampler defines the sampling policy in order to reduce the number of traces for instance */
-  final Sampler sampler;
   /** Scope manager is in charge of managing the scopes from which spans are created */
   final ContextualScopeManager scopeManager = new ContextualScopeManager();
 
@@ -113,15 +106,14 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
   }
 
   // This constructor is already used in the wild, so we have to keep it inside this API for now.
-  public DDTracer(final String serviceName, final Writer writer, final Sampler sampler) {
+  public DDTracer(final String serviceName, final Writer writer) {
-    this(serviceName, writer, sampler, Config.get().getLocalRootSpanTags());
+    this(serviceName, writer, Config.get().getLocalRootSpanTags());
   }
 
   private DDTracer(final String serviceName, final Config config) {
     this(
         serviceName,
         Writer.Builder.forConfig(config),
-        Sampler.Builder.forConfig(config),
         config.getLocalRootSpanTags(),
         config.getMergedSpanTags(),
         config.getServiceMapping(),
@@ -131,15 +123,10 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
   }
 
   /** Visible for testing */
-  DDTracer(
+  DDTracer(final String serviceName, final Writer writer, final Map<String, String> runtimeTags) {
-      final String serviceName,
-      final Writer writer,
-      final Sampler sampler,
-      final Map<String, String> runtimeTags) {
     this(
         serviceName,
         writer,
-        sampler,
         runtimeTags,
         Collections.<String, String>emptyMap(),
         Collections.<String, String>emptyMap(),
@@ -155,7 +142,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     this(
         config.getServiceName(),
         writer,
-        Sampler.Builder.forConfig(config),
         config.getLocalRootSpanTags(),
         config.getMergedSpanTags(),
         config.getServiceMapping(),
@@ -163,14 +149,11 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
         config.getPartialFlushMinSpans());
   }
 
-  /**
+  /** @deprecated Use {@link #DDTracer(String, Writer, Map, Map, Map, Map, int)} instead. */
-   * @deprecated Use {@link #DDTracer(String, Writer, Sampler, Map, Map, Map, Map, int)} instead.
-   */
   @Deprecated
   public DDTracer(
       final String serviceName,
       final Writer writer,
-      final Sampler sampler,
       final String runtimeId,
       final Map<String, String> localRootSpanTags,
       final Map<String, String> defaultSpanTags,
@@ -179,7 +162,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     this(
         serviceName,
         writer,
-        sampler,
         customRuntimeTags(runtimeId, localRootSpanTags),
         defaultSpanTags,
         serviceNameMappings,
@@ -187,14 +169,11 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
         Config.get().getPartialFlushMinSpans());
   }
 
-  /**
+  /** @deprecated Use {@link #DDTracer(String, Writer, Map, Map, Map, Map, int)} instead. */
-   * @deprecated Use {@link #DDTracer(String, Writer, Sampler, Map, Map, Map, Map, int)} instead.
-   */
   @Deprecated
   public DDTracer(
       final String serviceName,
       final Writer writer,
-      final Sampler sampler,
       final Map<String, String> localRootSpanTags,
       final Map<String, String> defaultSpanTags,
       final Map<String, String> serviceNameMappings,
@@ -202,7 +181,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     this(
         serviceName,
         writer,
-        sampler,
         localRootSpanTags,
         defaultSpanTags,
         serviceNameMappings,
@@ -213,7 +191,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
   public DDTracer(
       final String serviceName,
       final Writer writer,
-      final Sampler sampler,
       final Map<String, String> localRootSpanTags,
       final Map<String, String> defaultSpanTags,
       final Map<String, String> serviceNameMappings,
@@ -227,7 +204,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     this.serviceName = serviceName;
     this.writer = writer;
     this.writer.start();
-    this.sampler = sampler;
     this.localRootSpanTags = localRootSpanTags;
     this.defaultSpanTags = defaultSpanTags;
     this.serviceNameMappings = serviceNameMappings;
@@ -244,13 +220,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     injector = HttpCodec.createInjector(Config.get());
     extractor = HttpCodec.createExtractor(Config.get(), taggedHeaders);
 
-    if (this.writer instanceof DDAgentWriter) {
-      final DDApi api = ((DDAgentWriter) this.writer).getApi();
-      if (sampler instanceof DDApi.ResponseListener) {
-        api.addResponseListener((DDApi.ResponseListener) this.sampler);
-      }
-    }
-
     log.info("New instance: {}", this);
 
     final List<AbstractDecorator> decorators = DDDecoratorsFactory.createBuiltinDecorators();
@@ -363,12 +332,7 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     }
   }
 
-  /**
+  /** @param trace a list of the spans related to the same trace */
-   * We use the sampler to know if the trace has to be reported/written. The sampler is called on
-   * the first span (root span) of the trace. If the trace is marked as a sample, we report it.
-   *
-   * @param trace a list of the spans related to the same trace
-   */
   void write(final Collection<DDSpan> trace) {
     if (trace.isEmpty()) {
       return;
@@ -391,7 +355,7 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     incrementTraceCount();
     // TODO: current trace implementation doesn't guarantee that first span is the root span
     // We may want to reconsider way this check is done.
-    if (!writtenTrace.isEmpty() && sampler.sample(writtenTrace.get(0))) {
+    if (!writtenTrace.isEmpty()) {
       writer.write(writtenTrace);
     }
   }
@@ -443,8 +407,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
         + serviceName
         + ", writer="
         + writer
-        + ", sampler="
-        + sampler
         + ", defaultSpanTags="
         + defaultSpanTags
         + '}';
@@ -487,11 +449,7 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
     }
 
     private DDSpan startSpan() {
-      final DDSpan span = new DDSpan(timestampMicro, buildSpanContext());
+      return new DDSpan(timestampMicro, buildSpanContext());
-      if (sampler instanceof RateByServiceSampler) {
-        ((RateByServiceSampler) sampler).initializeSamplingPriority(span);
-      }
-      return span;
     }
 
     @Override
@@ -632,7 +590,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
       final BigInteger parentSpanId;
       final Map<String, String> baggage;
       final PendingTrace parentTrace;
-      final int samplingPriority;
       final String origin;
 
       final DDSpanContext context;
@@ -654,7 +611,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
         parentSpanId = ddsc.getSpanId();
         baggage = ddsc.getBaggageItems();
         parentTrace = ddsc.getTrace();
-        samplingPriority = PrioritySampling.UNSET;
         origin = null;
         if (serviceName == null) {
           serviceName = ddsc.getServiceName();
@@ -666,13 +622,11 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
           final ExtractedContext extractedContext = (ExtractedContext) parentContext;
           traceId = extractedContext.getTraceId();
           parentSpanId = extractedContext.getSpanId();
-          samplingPriority = extractedContext.getSamplingPriority();
           baggage = extractedContext.getBaggage();
         } else {
           // Start a new trace
           traceId = generateNewId();
           parentSpanId = BigInteger.ZERO;
-          samplingPriority = PrioritySampling.UNSET;
           baggage = null;
         }
 
@@ -704,7 +658,6 @@ public class DDTracer implements io.opentracing.Tracer, Closeable, datadog.trace
               serviceName,
               operationName,
               resourceName,
-              samplingPriority,
               origin,
               baggage,
               errorFlag,

dd-trace-ot/src/main/java/datadog/opentracing/PendingTrace.java

@@ -48,8 +48,7 @@ public class PendingTrace extends ConcurrentLinkedDeque<DDSpan> {
   // We must maintain a separate count because ConcurrentLinkedDeque.size() is a linear operation.
   private final AtomicInteger completedSpanCount = new AtomicInteger(0);
   /**
-   * During a trace there are cases where the root span must be accessed (e.g. priority sampling and
+   * During a trace there are cases where the root span must be accessed (e.g. trace-search tags).
-   * trace-search tags).
    *
    * <p>Use a weak ref because we still need to handle buggy cases where the root span is not
    * correctly closed (see SpanCleaner).

dd-trace-ot/src/main/java/datadog/opentracing/decorators/AnalyticsSampleRateDecorator.java

@@ -1,25 +0,0 @@
-package datadog.opentracing.decorators;
-
-import datadog.opentracing.DDSpanContext;
-import datadog.trace.api.DDTags;
-
-public class AnalyticsSampleRateDecorator extends AbstractDecorator {
-  public AnalyticsSampleRateDecorator() {
-    super();
-    setMatchingTag(DDTags.ANALYTICS_SAMPLE_RATE);
-  }
-
-  @Override
-  public boolean shouldSetTag(final DDSpanContext context, final String tag, final Object value) {
-    if (value instanceof Number) {
-      context.setMetric(DDTags.ANALYTICS_SAMPLE_RATE, (Number) value);
-    } else if (value instanceof String) {
-      try {
-        context.setMetric(DDTags.ANALYTICS_SAMPLE_RATE, Double.parseDouble((String) value));
-      } catch (final NumberFormatException ex) {
-        // ignore
-      }
-    }
-    return false;
-  }
-}

dd-trace-ot/src/main/java/datadog/opentracing/decorators/DDDecoratorsFactory.java

@@ -12,12 +12,9 @@ public class DDDecoratorsFactory {
     final List<AbstractDecorator> decorators =
         new ArrayList<>(
             Arrays.asList(
-                new AnalyticsSampleRateDecorator(),
                 new DBStatementAsResourceName(),
                 new DBTypeDecorator(),
                 new ErrorFlag(),
-                new ForceManualDropDecorator(),
-                new ForceManualKeepDecorator(),
                 new OperationDecorator(),
                 new PeerServiceDecorator(),
                 new ResourceNameDecorator(),

dd-trace-ot/src/main/java/datadog/opentracing/decorators/ForceManualDropDecorator.java

@@ -1,26 +0,0 @@
-package datadog.opentracing.decorators;
-
-import datadog.opentracing.DDSpanContext;
-import datadog.trace.api.DDTags;
-import datadog.trace.api.sampling.PrioritySampling;
-
-/**
- * Tag decorator to replace tag 'manual.drop: true' with the appropriate priority sampling value.
- */
-public class ForceManualDropDecorator extends AbstractDecorator {
-
-  public ForceManualDropDecorator() {
-    super();
-    setMatchingTag(DDTags.MANUAL_DROP);
-  }
-
-  @Override
-  public boolean shouldSetTag(final DDSpanContext context, final String tag, final Object value) {
-    if (value instanceof Boolean && (boolean) value) {
-      context.setSamplingPriority(PrioritySampling.USER_DROP);
-    } else if (value instanceof String && Boolean.parseBoolean((String) value)) {
-      context.setSamplingPriority(PrioritySampling.USER_DROP);
-    }
-    return false;
-  }
-}

dd-trace-ot/src/main/java/datadog/opentracing/decorators/ForceManualKeepDecorator.java

@@ -1,26 +0,0 @@
-package datadog.opentracing.decorators;
-
-import datadog.opentracing.DDSpanContext;
-import datadog.trace.api.DDTags;
-import datadog.trace.api.sampling.PrioritySampling;
-
-/**
- * Tag decorator to replace tag 'manual.keep: true' with the appropriate priority sampling value.
- */
-public class ForceManualKeepDecorator extends AbstractDecorator {
-
-  public ForceManualKeepDecorator() {
-    super();
-    setMatchingTag(DDTags.MANUAL_KEEP);
-  }
-
-  @Override
-  public boolean shouldSetTag(final DDSpanContext context, final String tag, final Object value) {
-    if (value instanceof Boolean && (boolean) value) {
-      context.setSamplingPriority(PrioritySampling.USER_KEEP);
-    } else if (value instanceof String && Boolean.parseBoolean((String) value)) {
-      context.setSamplingPriority(PrioritySampling.USER_KEEP);
-    }
-    return false;
-  }
-}

dd-trace-ot/src/main/java/datadog/opentracing/propagation/B3HttpCodec.java

@@ -3,7 +3,6 @@ package datadog.opentracing.propagation;
 import static datadog.opentracing.propagation.HttpCodec.validateUInt64BitsID;
 
 import datadog.opentracing.DDSpanContext;
-import datadog.trace.api.sampling.PrioritySampling;
 import io.opentracing.SpanContext;
 import io.opentracing.propagation.TextMapExtract;
 import io.opentracing.propagation.TextMapInject;
@@ -25,9 +24,6 @@ class B3HttpCodec {
 
   private static final String TRACE_ID_KEY = "X-B3-TraceId";
   private static final String SPAN_ID_KEY = "X-B3-SpanId";
-  private static final String SAMPLING_PRIORITY_KEY = "X-B3-Sampled";
-  private static final String SAMPLING_PRIORITY_ACCEPT = String.valueOf(1);
-  private static final String SAMPLING_PRIORITY_DROP = String.valueOf(0);
   private static final int HEX_RADIX = 16;
 
   private B3HttpCodec() {
@@ -41,21 +37,12 @@ class B3HttpCodec {
       try {
         carrier.put(TRACE_ID_KEY, context.getTraceId().toString(HEX_RADIX).toLowerCase());
         carrier.put(SPAN_ID_KEY, context.getSpanId().toString(HEX_RADIX).toLowerCase());
-
-        if (context.lockSamplingPriority()) {
-          carrier.put(
-              SAMPLING_PRIORITY_KEY, convertSamplingPriority(context.getSamplingPriority()));
-        }
         log.debug("{} - B3 parent context injected", context.getTraceId());
       } catch (final NumberFormatException e) {
         log.debug(
             "Cannot parse context id(s): {} {}", context.getTraceId(), context.getSpanId(), e);
       }
     }
-
-    private String convertSamplingPriority(final int samplingPriority) {
-      return samplingPriority > 0 ? SAMPLING_PRIORITY_ACCEPT : SAMPLING_PRIORITY_DROP;
-    }
   }
 
   public static class Extractor implements HttpCodec.Extractor {
@@ -75,7 +62,6 @@ class B3HttpCodec {
         Map<String, String> tags = Collections.emptyMap();
         BigInteger traceId = BigInteger.ZERO;
         BigInteger spanId = BigInteger.ZERO;
-        int samplingPriority = PrioritySampling.UNSET;
 
         for (final Map.Entry<String, String> entry : carrier) {
           final String key = entry.getKey().toLowerCase();
@@ -100,8 +86,6 @@ class B3HttpCodec {
             traceId = validateUInt64BitsID(trimmedValue, HEX_RADIX);
           } else if (SPAN_ID_KEY.equalsIgnoreCase(key)) {
             spanId = validateUInt64BitsID(value, HEX_RADIX);
-          } else if (SAMPLING_PRIORITY_KEY.equalsIgnoreCase(key)) {
-            samplingPriority = convertSamplingPriority(value);
           }
 
           if (taggedHeaders.containsKey(key)) {
@@ -115,13 +99,7 @@ class B3HttpCodec {
         if (!BigInteger.ZERO.equals(traceId)) {
           final ExtractedContext context =
               new ExtractedContext(
-                  traceId,
+                  traceId, spanId, null, Collections.<String, String>emptyMap(), tags);
-                  spanId,
-                  samplingPriority,
-                  null,
-                  Collections.<String, String>emptyMap(),
-                  tags);
-          context.lockSamplingPriority();
 
           log.debug("{} - Parent context extracted", context.getTraceId());
           return context;
@@ -135,11 +113,5 @@ class B3HttpCodec {
 
       return null;
     }
-
-    private int convertSamplingPriority(final String samplingPriority) {
-      return Integer.parseInt(samplingPriority) == 1
-          ? PrioritySampling.SAMPLER_KEEP
-          : PrioritySampling.SAMPLER_DROP;
-    }
   }
 }

dd-trace-ot/src/main/java/datadog/opentracing/propagation/DatadogHttpCodec.java

@@ -3,7 +3,6 @@ package datadog.opentracing.propagation;
 import static datadog.opentracing.propagation.HttpCodec.validateUInt64BitsID;
 
 import datadog.opentracing.DDSpanContext;
-import datadog.trace.api.sampling.PrioritySampling;
 import io.opentracing.SpanContext;
 import io.opentracing.propagation.TextMapExtract;
 import io.opentracing.propagation.TextMapInject;
@@ -20,7 +19,6 @@ class DatadogHttpCodec {
   private static final String OT_BAGGAGE_PREFIX = "ot-baggage-";
   private static final String TRACE_ID_KEY = "x-datadog-trace-id";
   private static final String SPAN_ID_KEY = "x-datadog-parent-id";
-  private static final String SAMPLING_PRIORITY_KEY = "x-datadog-sampling-priority";
   private static final String ORIGIN_KEY = "x-datadog-origin";
 
   private DatadogHttpCodec() {
@@ -33,9 +31,6 @@ class DatadogHttpCodec {
     public void inject(final DDSpanContext context, final TextMapInject carrier) {
       carrier.put(TRACE_ID_KEY, context.getTraceId().toString());
       carrier.put(SPAN_ID_KEY, context.getSpanId().toString());
-      if (context.lockSamplingPriority()) {
-        carrier.put(SAMPLING_PRIORITY_KEY, String.valueOf(context.getSamplingPriority()));
-      }
       final String origin = context.getOrigin();
       if (origin != null) {
         carrier.put(ORIGIN_KEY, origin);
@@ -65,7 +60,6 @@ class DatadogHttpCodec {
         Map<String, String> tags = Collections.emptyMap();
         BigInteger traceId = BigInteger.ZERO;
         BigInteger spanId = BigInteger.ZERO;
-        int samplingPriority = PrioritySampling.UNSET;
         String origin = null;
 
         for (final Map.Entry<String, String> entry : carrier) {
@@ -80,8 +74,6 @@ class DatadogHttpCodec {
             traceId = validateUInt64BitsID(value, 10);
           } else if (SPAN_ID_KEY.equalsIgnoreCase(key)) {
             spanId = validateUInt64BitsID(value, 10);
-          } else if (SAMPLING_PRIORITY_KEY.equalsIgnoreCase(key)) {
-            samplingPriority = Integer.parseInt(value);
           } else if (ORIGIN_KEY.equalsIgnoreCase(key)) {
             origin = value;
           } else if (key.startsWith(OT_BAGGAGE_PREFIX)) {
@@ -101,8 +93,7 @@ class DatadogHttpCodec {
 
         if (!BigInteger.ZERO.equals(traceId)) {
           final ExtractedContext context =
-              new ExtractedContext(traceId, spanId, samplingPriority, origin, baggage, tags);
+              new ExtractedContext(traceId, spanId, origin, baggage, tags);
-          context.lockSamplingPriority();
 
           log.debug("{} - Parent context extracted", context.getTraceId());
           return context;

dd-trace-ot/src/main/java/datadog/opentracing/propagation/ExtractedContext.java

@@ -2,7 +2,6 @@ package datadog.opentracing.propagation;
 
 import java.math.BigInteger;
 import java.util.Map;
-import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
  * Propagated data resulting from calling tracer.extract with header data from an incoming request.
@@ -10,21 +9,17 @@ import java.util.concurrent.atomic.AtomicBoolean;
 public class ExtractedContext extends TagContext {
   private final BigInteger traceId;
   private final BigInteger spanId;
-  private final int samplingPriority;
   private final Map<String, String> baggage;
-  private final AtomicBoolean samplingPriorityLocked = new AtomicBoolean(false);
 
   public ExtractedContext(
       final BigInteger traceId,
       final BigInteger spanId,
-      final int samplingPriority,
       final String origin,
       final Map<String, String> baggage,
       final Map<String, String> tags) {
     super(origin, tags);
     this.traceId = traceId;
     this.spanId = spanId;
-    this.samplingPriority = samplingPriority;
     this.baggage = baggage;
   }
 
@@ -33,10 +28,6 @@ public class ExtractedContext extends TagContext {
     return baggage.entrySet();
   }
 
-  public void lockSamplingPriority() {
-    samplingPriorityLocked.set(true);
-  }
-
   public BigInteger getTraceId() {
     return traceId;
   }
@@ -45,15 +36,7 @@ public class ExtractedContext extends TagContext {
     return spanId;
   }
 
-  public int getSamplingPriority() {
-    return samplingPriority;
-  }
-
   public Map<String, String> getBaggage() {
     return baggage;
   }
-
-  public boolean getSamplingPriorityLocked() {
-    return samplingPriorityLocked.get();
-  }
 }

dd-trace-ot/src/main/java/datadog/opentracing/propagation/HaystackHttpCodec.java

@@ -3,7 +3,6 @@ package datadog.opentracing.propagation;
 import static datadog.opentracing.propagation.HttpCodec.validateUInt64BitsID;
 
 import datadog.opentracing.DDSpanContext;
-import datadog.trace.api.sampling.PrioritySampling;
 import io.opentracing.SpanContext;
 import io.opentracing.propagation.TextMapExtract;
 import io.opentracing.propagation.TextMapInject;
@@ -63,7 +62,6 @@ public class HaystackHttpCodec {
         Map<String, String> tags = Collections.emptyMap();
         BigInteger traceId = BigInteger.ZERO;
         BigInteger spanId = BigInteger.ZERO;
-        final int samplingPriority = PrioritySampling.SAMPLER_KEEP;
         final String origin = null; // Always null
 
         for (final Map.Entry<String, String> entry : carrier) {
@@ -95,8 +93,7 @@ public class HaystackHttpCodec {
 
         if (!BigInteger.ZERO.equals(traceId)) {
           final ExtractedContext context =
-              new ExtractedContext(traceId, spanId, samplingPriority, origin, baggage, tags);
+              new ExtractedContext(traceId, spanId, origin, baggage, tags);
-          context.lockSamplingPriority();
 
           log.debug("{} - Parent context extracted", context.getTraceId());
           return context;

dd-trace-ot/src/main/java/datadog/trace/common/sampling/AbstractSampler.java

@@ -1,43 +0,0 @@
-package datadog.trace.common.sampling;
-
-import datadog.opentracing.DDSpan;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.regex.Pattern;
-
-public abstract class AbstractSampler implements Sampler {
-
-  /** Sample tags */
-  protected Map<String, Pattern> skipTagsPatterns = new HashMap<>();
-
-  @Override
-  public boolean sample(final DDSpan span) {
-
-    // Filter by tag values
-    for (final Entry<String, Pattern> entry : skipTagsPatterns.entrySet()) {
-      final Object value = span.getTags().get(entry.getKey());
-      if (value != null) {
-        final String strValue = String.valueOf(value);
-        final Pattern skipPattern = entry.getValue();
-        if (skipPattern.matcher(strValue).matches()) {
-          return false;
-        }
-      }
-    }
-
-    return doSample(span);
-  }
-
-  /**
-   * Pattern based skipping of tag values
-   *
-   * @param tag
-   * @param skipPattern
-   */
-  public void addSkipTagPattern(final String tag, final Pattern skipPattern) {
-    skipTagsPatterns.put(tag, skipPattern);
-  }
-
-  protected abstract boolean doSample(DDSpan span);
-}

dd-trace-ot/src/main/java/datadog/trace/common/sampling/AllSampler.java

@@ -1,17 +0,0 @@
-package datadog.trace.common.sampling;
-
-import datadog.opentracing.DDSpan;
-
-/** Sampler that always says yes... */
-public class AllSampler extends AbstractSampler {
-
-  @Override
-  public boolean doSample(final DDSpan span) {
-    return true;
-  }
-
-  @Override
-  public String toString() {
-    return "AllSampler { sample=true }";
-  }
-}

dd-trace-ot/src/main/java/datadog/trace/common/sampling/PrioritySampling.java

@@ -1,22 +0,0 @@
-package datadog.trace.common.sampling;
-
-/** @deprecated Replaced by {@link datadog.trace.api.sampling.PrioritySampling} . */
-@Deprecated
-public class PrioritySampling {
-  /**
-   * Implementation detail of the client. will not be sent to the agent or propagated.
-   *
-   * <p>Internal value used when the priority sampling flag has not been set on the span context.
-   */
-  public static final int UNSET = Integer.MIN_VALUE;
-  /** The sampler has decided to drop the trace. */
-  public static final int SAMPLER_DROP = 0;
-  /** The sampler has decided to keep the trace. */
-  public static final int SAMPLER_KEEP = 1;
-  /** The user has decided to drop the trace. */
-  public static final int USER_DROP = -1;
-  /** The user has decided to keep the trace. */
-  public static final int USER_KEEP = 2;
-
-  private PrioritySampling() {}
-}

dd-trace-ot/src/main/java/datadog/trace/common/sampling/RateByServiceSampler.java

@@ -1,145 +0,0 @@
-package datadog.trace.common.sampling;
-
-import static java.util.Collections.singletonMap;
-import static java.util.Collections.unmodifiableMap;
-
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.node.NumericNode;
-import datadog.opentracing.DDSpan;
-import datadog.trace.api.sampling.PrioritySampling;
-import datadog.trace.common.writer.DDApi.ResponseListener;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.Map;
-import java.util.concurrent.ThreadLocalRandom;
-import lombok.extern.slf4j.Slf4j;
-
-/**
- * A rate sampler which maintains different sample rates per service+env name.
- *
- * <p>The configuration of (serviceName,env)->rate is configured by the core agent.
- */
-@Slf4j
-public class RateByServiceSampler implements Sampler, ResponseListener {
-  /** Key for setting the default/baseline rate */
-  private static final String DEFAULT_KEY = "service:,env:";
-
-  private static final double DEFAULT_RATE = 1.0;
-
-  private volatile Map<String, RateSampler> serviceRates =
-      unmodifiableMap(singletonMap(DEFAULT_KEY, new RateSampler(DEFAULT_RATE)));
-
-  @Override
-  public boolean sample(final DDSpan span) {
-    // Priority sampling sends all traces to the core agent, including traces marked dropped.
-    // This allows the core agent to collect stats on all traces.
-    return true;
-  }
-
-  /** If span is a root span, set the span context samplingPriority to keep or drop */
-  public void initializeSamplingPriority(final DDSpan span) {
-    if (span.isRootSpan()) {
-      // Run the priority sampler on the new span
-      setSamplingPriorityOnSpanContext(span);
-    } else if (span.getSamplingPriority() == null) {
-      // Edge case: If the parent context did not set the priority, run the priority sampler.
-      // Happens when extracted http context did not send the priority header.
-      setSamplingPriorityOnSpanContext(span);
-    }
-  }
-
-  private void setSamplingPriorityOnSpanContext(final DDSpan span) {
-    final String serviceName = span.getServiceName();
-    final String env = getSpanEnv(span);
-    final String key = "service:" + serviceName + ",env:" + env;
-
-    final Map<String, RateSampler> rates = serviceRates;
-    RateSampler sampler = serviceRates.get(key);
-    if (sampler == null) {
-      sampler = rates.get(DEFAULT_KEY);
-    }
-
-    if (sampler.sample(span)) {
-      span.setSamplingPriority(PrioritySampling.SAMPLER_KEEP);
-    } else {
-      span.setSamplingPriority(PrioritySampling.SAMPLER_DROP);
-    }
-  }
-
-  private static String getSpanEnv(final DDSpan span) {
-    return null == span.getTags().get("env") ? "" : String.valueOf(span.getTags().get("env"));
-  }
-
-  @Override
-  public void onResponse(final String endpoint, final JsonNode responseJson) {
-    final JsonNode newServiceRates = responseJson.get("rate_by_service");
-    if (null != newServiceRates) {
-      log.debug("Update service sampler rates: {} -> {}", endpoint, responseJson);
-      final Map<String, RateSampler> updatedServiceRates = new HashMap<>();
-      final Iterator<String> itr = newServiceRates.fieldNames();
-      while (itr.hasNext()) {
-        final String key = itr.next();
-        final JsonNode value = newServiceRates.get(key);
-        try {
-          if (value instanceof NumericNode) {
-            updatedServiceRates.put(key, new RateSampler(value.doubleValue()));
-          } else {
-            log.debug("Unable to parse new service rate {} -> {}", key, value);
-          }
-        } catch (final NumberFormatException nfe) {
-          log.debug("Unable to parse new service rate {} -> {}", key, value);
-        }
-      }
-      if (!updatedServiceRates.containsKey(DEFAULT_KEY)) {
-        updatedServiceRates.put(DEFAULT_KEY, new RateSampler(DEFAULT_RATE));
-      }
-      serviceRates = unmodifiableMap(updatedServiceRates);
-    }
-  }
-
-  /**
-   * This sampler sample the traces at a predefined rate.
-   *
-   * <p>Keep (100 * `sample_rate`)% of the traces. It samples randomly, its main purpose is to
-   * reduce the integration footprint.
-   */
-  private static class RateSampler extends AbstractSampler {
-
-    /** The sample rate used */
-    private final double sampleRate;
-
-    /**
-     * Build an instance of the sampler. The Sample rate is fixed for each instance.
-     *
-     * @param sampleRate a number [0,1] representing the rate ratio.
-     */
-    private RateSampler(double sampleRate) {
-
-      if (sampleRate < 0) {
-        sampleRate = 1;
-        log.error("SampleRate is negative or null, disabling the sampler");
-      } else if (sampleRate > 1) {
-        sampleRate = 1;
-      }
-
-      this.sampleRate = sampleRate;
-      log.debug("Initializing the RateSampler, sampleRate: {} %", this.sampleRate * 100);
-    }
-
-    @Override
-    public boolean doSample(final DDSpan span) {
-      final boolean sample = ThreadLocalRandom.current().nextFloat() <= sampleRate;
-      log.debug("{} - Span is sampled: {}", span, sample);
-      return sample;
-    }
-
-    public double getSampleRate() {
-      return sampleRate;
-    }
-
-    @Override
-    public String toString() {
-      return "RateSampler { sampleRate=" + sampleRate + " }";
-    }
-  }
-}

dd-trace-ot/src/main/java/datadog/trace/common/sampling/Sampler.java

@@ -1,39 +0,0 @@
-package datadog.trace.common.sampling;
-
-import datadog.opentracing.DDSpan;
-import datadog.trace.api.Config;
-import java.util.Properties;
-
-/** Main interface to sample a collection of traces. */
-public interface Sampler {
-
-  /**
-   * Sample a collection of traces based on the parent span
-   *
-   * @param span the parent span with its context
-   * @return true when the trace/spans has to be reported/written
-   */
-  boolean sample(DDSpan span);
-
-  final class Builder {
-    public static Sampler forConfig(final Config config) {
-      final Sampler sampler;
-      if (config != null) {
-        if (config.isPrioritySamplingEnabled()) {
-          sampler = new RateByServiceSampler();
-        } else {
-          sampler = new AllSampler();
-        }
-      } else {
-        sampler = new AllSampler();
-      }
-      return sampler;
-    }
-
-    public static Sampler forConfig(final Properties config) {
-      return forConfig(Config.get(config));
-    }
-
-    private Builder() {}
-  }
-}

dd-trace-ot/src/main/java/datadog/trace/common/writer/DDAgentWriter.java

@@ -35,7 +35,7 @@ import lombok.extern.slf4j.Slf4j;
  *
  * <p>Written traces are passed off to a disruptor so as to avoid blocking the application's thread.
  * If a flood of traces arrives that exceeds the disruptor ring size, the traces exceeding the
- * threshold will be counted and sampled.
+ * threshold will be counted.
  */
 @Slf4j
 public class DDAgentWriter implements Writer {

dd-trace-ot/src/ot31CompatabilityTest/groovy/OT31ApiTest.groovy

@@ -70,9 +70,8 @@ class OT31ApiTest extends DDSpecification {
 
     then:
     textMap == [
-      "x-datadog-trace-id"         : context.toTraceId(),
+      "x-datadog-trace-id" : context.toTraceId(),
-      "x-datadog-parent-id"        : context.toSpanId(),
+      "x-datadog-parent-id": context.toSpanId(),
-      "x-datadog-sampling-priority": "$context.samplingPriority",
     ]
 
     when:
@@ -81,7 +80,6 @@ class OT31ApiTest extends DDSpecification {
     then:
     extract.traceId == context.traceId
     extract.spanId == context.spanId
-    extract.samplingPriority == context.samplingPriority
   }
 
   static class TextMapAdapter implements TextMap {

dd-trace-ot/src/test/groovy/datadog/opentracing/DDSpanBuilderTest.groovy

@@ -4,7 +4,6 @@ import datadog.opentracing.propagation.ExtractedContext
 import datadog.opentracing.propagation.TagContext
 import datadog.trace.api.Config
 import datadog.trace.api.DDTags
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.Scope
@@ -421,7 +420,6 @@ class DDSpanBuilderTest extends DDSpecification {
     expect:
     span.traceId == extractedContext.traceId
     span.parentId == extractedContext.spanId
-    span.samplingPriority == extractedContext.samplingPriority
     span.context().origin == extractedContext.origin
     span.context().baggageItems == extractedContext.baggage
     span.context().@tags == extractedContext.tags + [(Config.RUNTIME_ID_TAG)  : config.getRuntimeId(),
@@ -430,8 +428,8 @@ class DDSpanBuilderTest extends DDSpecification {
 
     where:
     extractedContext                                                                                                | _
-    new ExtractedContext(1G, 2G, 0, null, [:], [:])                                                                 | _
+    new ExtractedContext(1G, 2G, null, [:], [:])                                                                 | _
-    new ExtractedContext(3G, 4G, 1, "some-origin", ["asdf": "qwer"], [(ORIGIN_KEY): "some-origin", "zxcv": "1234"]) | _
+    new ExtractedContext(3G, 4G, "some-origin", ["asdf": "qwer"], [(ORIGIN_KEY): "some-origin", "zxcv": "1234"]) | _
   }
 
   def "TagContext should populate default span details"() {
@@ -442,7 +440,6 @@ class DDSpanBuilderTest extends DDSpecification {
     expect:
     span.traceId != 0G
     span.parentId == 0G
-    span.samplingPriority == PrioritySampling.SAMPLER_KEEP // Since we're using the RateByServiceSampler
     span.context().origin == tagContext.origin
     span.context().baggageItems == [:]
     span.context().@tags == tagContext.tags + [(Config.RUNTIME_ID_TAG)  : config.getRuntimeId(),

dd-trace-ot/src/test/groovy/datadog/opentracing/DDSpanSerializationTest.groovy

@@ -1,9 +1,6 @@
 package datadog.opentracing
 
 import com.fasterxml.jackson.databind.ObjectMapper
-import com.google.common.collect.Maps
-import datadog.trace.api.DDTags
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import org.msgpack.core.MessagePack
@@ -13,72 +10,6 @@ import org.msgpack.value.ValueType
 
 class DDSpanSerializationTest extends DDSpecification {
 
-  def "serialize spans with sampling #samplingPriority"() throws Exception {
-    setup:
-    final Map<String, String> baggage = new HashMap<>()
-    baggage.put("a-baggage", "value")
-    final Map<String, Object> tags = new HashMap<>()
-    baggage.put("k1", "v1")
-
-    Map<String, Object> expected = Maps.newHashMap()
-    expected.put("meta", baggage)
-    expected.put("service", "service")
-    expected.put("error", 0)
-    expected.put("type", "type")
-    expected.put("name", "operation")
-    expected.put("duration", 33000)
-    expected.put("resource", "operation")
-    final Map<String, Number> metrics = new HashMap<>()
-    if (samplingPriority != PrioritySampling.UNSET) {
-      metrics.put("_sampling_priority_v1", Integer.valueOf(samplingPriority))
-      metrics.put("_sample_rate", Double.valueOf(1.0))
-    }
-    expected.put("metrics", metrics)
-    expected.put("start", 100000)
-    expected.put("span_id", 2l)
-    expected.put("parent_id", 0l)
-    expected.put("trace_id", 1l)
-
-    def writer = new ListWriter()
-    def tracer = new DDTracer(writer)
-    final DDSpanContext context =
-      new DDSpanContext(
-        1G,
-        2G,
-        0G,
-        "service",
-        "operation",
-        null,
-        samplingPriority,
-        null,
-        new HashMap<>(baggage),
-        false,
-        "type",
-        tags,
-        new PendingTrace(tracer, 1G, [:]),
-        tracer)
-
-    baggage.put(DDTags.THREAD_NAME, Thread.currentThread().getName())
-    baggage.put(DDTags.THREAD_ID, String.valueOf(Thread.currentThread().getId()))
-
-    DDSpan span = new DDSpan(100L, context)
-    if (samplingPriority != PrioritySampling.UNSET) {
-      span.context().setMetric("_sample_rate", Double.valueOf(1.0))
-    }
-    span.finish(133L)
-    ObjectMapper serializer = new ObjectMapper()
-
-    def actualTree = serializer.readTree(serializer.writeValueAsString(span))
-    def expectedTree = serializer.readTree(serializer.writeValueAsString(expected))
-    expect:
-    actualTree == expectedTree
-
-    where:
-    samplingPriority              | _
-    PrioritySampling.SAMPLER_KEEP | _
-    PrioritySampling.UNSET        | _
-  }
-
   def "serialize trace/span with id #value as int"() {
     setup:
     def objectMapper = new ObjectMapper(new MessagePackFactory())
@@ -91,7 +22,6 @@ class DDSpanSerializationTest extends DDSpecification {
       "fakeService",
       "fakeOperation",
       "fakeResource",
-      PrioritySampling.UNSET,
       null,
       Collections.emptyMap(),
       false,

dd-trace-ot/src/test/groovy/datadog/opentracing/DDSpanTest.groovy

@@ -1,15 +1,11 @@
 package datadog.opentracing
 
-import com.fasterxml.jackson.databind.ObjectMapper
+
 import datadog.opentracing.propagation.ExtractedContext
 import datadog.opentracing.propagation.TagContext
-import datadog.trace.api.DDTags
-import datadog.trace.api.sampling.PrioritySampling
-import datadog.trace.common.sampling.RateByServiceSampler
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.SpanContext
-import spock.lang.Shared
 
 import java.util.concurrent.TimeUnit
 
@@ -18,16 +14,7 @@ import static datadog.trace.api.Config.DEFAULT_SERVICE_NAME
 class DDSpanTest extends DDSpecification {
 
   def writer = new ListWriter()
-  def sampler = new RateByServiceSampler()
+  def tracer = new DDTracer(DEFAULT_SERVICE_NAME, writer, [:])
-  def tracer = new DDTracer(DEFAULT_SERVICE_NAME, writer, sampler, [:])
-
-  @Shared
-  def defaultSamplingPriority = PrioritySampling.SAMPLER_KEEP
-
-  def setup() {
-    sampler.onResponse("test", new ObjectMapper()
-      .readTree('{"rate_by_service":{"service:,env:":1.0,"service:spock,env:":0.0}}'))
-  }
 
   def "getters and setters"() {
     setup:
@@ -39,7 +26,6 @@ class DDSpanTest extends DDSpecification {
         "fakeService",
         "fakeOperation",
         "fakeResource",
-        PrioritySampling.UNSET,
         null,
         Collections.<String, String> emptyMap(),
         false,
@@ -69,22 +55,6 @@ class DDSpanTest extends DDSpecification {
     span.setSpanType("type")
     then:
     span.getType() == "type"
-
-    when:
-    span.setSamplingPriority(PrioritySampling.UNSET)
-    then:
-    span.getSamplingPriority() == null
-
-    when:
-    span.setSamplingPriority(PrioritySampling.SAMPLER_KEEP)
-    then:
-    span.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
-
-    when:
-    context.lockSamplingPriority()
-    span.setSamplingPriority(PrioritySampling.USER_KEEP)
-    then:
-    span.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
   }
 
   def "resource name equals operation name if null"() {
@@ -178,28 +148,6 @@ class DDSpanTest extends DDSpecification {
     span.durationNano == 1
   }
 
-  def "priority sampling metric set only on root span"() {
-    setup:
-    def parent = tracer.buildSpan("testParent").start()
-    def child1 = tracer.buildSpan("testChild1").asChildOf(parent).start()
-
-    child1.setSamplingPriority(PrioritySampling.SAMPLER_KEEP)
-    child1.context().lockSamplingPriority()
-    parent.setSamplingPriority(PrioritySampling.SAMPLER_DROP)
-    child1.finish()
-    def child2 = tracer.buildSpan("testChild2").asChildOf(parent).start()
-    child2.finish()
-    parent.finish()
-
-    expect:
-    parent.context().samplingPriority == PrioritySampling.SAMPLER_KEEP
-    parent.getMetrics().get(DDSpanContext.PRIORITY_SAMPLING_KEY) == PrioritySampling.SAMPLER_KEEP
-    child1.getSamplingPriority() == parent.getSamplingPriority()
-    child1.getMetrics().get(DDSpanContext.PRIORITY_SAMPLING_KEY) == null
-    child2.getSamplingPriority() == parent.getSamplingPriority()
-    child2.getMetrics().get(DDSpanContext.PRIORITY_SAMPLING_KEY) == null
-  }
-
   def "origin set only on root span"() {
     setup:
     def parent = tracer.buildSpan("testParent").asChildOf(extractedContext).start().context()
@@ -212,9 +160,9 @@ class DDSpanTest extends DDSpecification {
     child.@origin == null // Access field directly instead of getter.
 
     where:
-    extractedContext                                         | _
+    extractedContext                                      | _
-    new TagContext("some-origin", [:])                       | _
+    new TagContext("some-origin", [:])                    | _
-    new ExtractedContext(1G, 2G, 0, "some-origin", [:], [:]) | _
+    new ExtractedContext(1G, 2G, "some-origin", [:], [:]) | _
   }
 
   def "isRootSpan() in and not in the context of distributed tracing"() {
@@ -231,9 +179,9 @@ class DDSpanTest extends DDSpecification {
     root.finish()
 
     where:
-    extractedContext                                     | isTraceRootSpan
+    extractedContext                                  | isTraceRootSpan
-    null                                                 | true
+    null                                              | true
-    new ExtractedContext(123G, 456G, 1, "789", [:], [:]) | false
+    new ExtractedContext(123G, 456G, "789", [:], [:]) | false
   }
 
   def "getApplicationRootSpan() in and not in the context of distributed tracing"() {
@@ -253,74 +201,8 @@ class DDSpanTest extends DDSpecification {
     root.finish()
 
     where:
-    extractedContext                                     | isTraceRootSpan
+    extractedContext                                  | isTraceRootSpan
-    null                                                 | true
+    null                                              | true
-    new ExtractedContext(123G, 456G, 1, "789", [:], [:]) | false
+    new ExtractedContext(123G, 456G, "789", [:], [:]) | false
-  }
-
-  def "sampling priority set on init"() {
-    setup:
-    def span = tracer.buildSpan("test").start()
-
-    expect:
-    span.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
-
-    when:
-    span.setTag(DDTags.SERVICE_NAME, "spock")
-
-    then:
-    // FIXME: priority currently only applies if service name set before span started.
-    span.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
-//    span.getSamplingPriority() == PrioritySampling.SAMPLER_DROP
-
-    when:
-    span = tracer.buildSpan("test").withTag(DDTags.SERVICE_NAME, "spock").start()
-
-    then:
-    span.getSamplingPriority() == PrioritySampling.SAMPLER_DROP
-  }
-
-  def "setting forced tracing via tag"() {
-    setup:
-    def span = tracer.buildSpan("root").start()
-    if (tagName) {
-      span.setTag(tagName, tagValue)
-    }
-
-    expect:
-    span.getSamplingPriority() == expectedPriority
-
-    cleanup:
-    span.finish()
-
-    where:
-    tagName       | tagValue | expectedPriority
-    'manual.drop' | true     | PrioritySampling.USER_DROP
-    'manual.keep' | true     | PrioritySampling.USER_KEEP
-  }
-
-  def "not setting forced tracing via tag or setting it wrong value not causing exception"() {
-
-    setup:
-    def span = tracer.buildSpan("root").start()
-    if (tagName) {
-      span.setTag(tagName, tagValue)
-    }
-
-    expect:
-    span.getSamplingPriority() == defaultSamplingPriority
-
-    cleanup:
-    span.finish()
-
-    where:
-    tagName       | tagValue
-    // When no tag is set default to
-    null          | null
-    // Setting to not known value
-    'manual.drop' | false
-    'manual.keep' | false
-    'manual.drop' | 1
-    'manual.keep' | 1
   }
 }

dd-trace-ot/src/test/groovy/datadog/opentracing/SpanFactory.groovy

@@ -1,7 +1,6 @@
 package datadog.opentracing
 
 
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 
 class SpanFactory {
@@ -18,7 +17,6 @@ class SpanFactory {
       "fakeService",
       "fakeOperation",
       "fakeResource",
-      PrioritySampling.UNSET,
       null,
       Collections.emptyMap(),
       false,
@@ -38,7 +36,6 @@ class SpanFactory {
       "fakeService",
       "fakeOperation",
       "fakeResource",
-      PrioritySampling.UNSET,
       null,
       Collections.emptyMap(),
       false,
@@ -57,7 +54,6 @@ class SpanFactory {
       "fakeService",
       "fakeOperation",
       "fakeResource",
-      PrioritySampling.UNSET,
       null,
       Collections.emptyMap(),
       false,
@@ -78,7 +74,6 @@ class SpanFactory {
       serviceName,
       "fakeOperation",
       "fakeResource",
-      PrioritySampling.UNSET,
       null,
       Collections.emptyMap(),
       false,

dd-trace-ot/src/test/groovy/datadog/opentracing/decorators/SpanDecoratorTest.groovy

@@ -7,15 +7,12 @@ import datadog.trace.agent.test.utils.ConfigUtils
 import datadog.trace.api.Config
 import datadog.trace.api.DDSpanTypes
 import datadog.trace.api.DDTags
-import datadog.trace.api.sampling.PrioritySampling
-import datadog.trace.common.sampling.AllSampler
 import datadog.trace.common.writer.LoggingWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.tag.StringTag
 import io.opentracing.tag.Tags
 
 import static datadog.trace.api.Config.DEFAULT_SERVICE_NAME
-import static datadog.trace.api.DDTags.ANALYTICS_SAMPLE_RATE
 import static java.util.Collections.emptyMap
 
 class SpanDecoratorTest extends DDSpecification {
@@ -58,7 +55,6 @@ class SpanDecoratorTest extends DDSpecification {
     tracer = new DDTracer(
       "wrong-service",
       new LoggingWriter(),
-      new AllSampler(),
       "some-runtime-id",
       emptyMap(),
       emptyMap(),
@@ -94,7 +90,6 @@ class SpanDecoratorTest extends DDSpecification {
     tracer = new DDTracer(
       serviceName,
       new LoggingWriter(),
-      new AllSampler(),
       "some-runtime-id",
       emptyMap(),
       emptyMap(),
@@ -141,7 +136,6 @@ class SpanDecoratorTest extends DDSpecification {
     tracer = new DDTracer(
       serviceName,
       new LoggingWriter(),
-      new AllSampler(),
       "some-runtime-id",
       emptyMap(),
       emptyMap(),
@@ -225,58 +219,6 @@ class SpanDecoratorTest extends DDSpecification {
     type = "foo"
   }
 
-  def "span metrics starts empty but added with rate limiting value of #rate"() {
-    expect:
-    span.metrics == [:]
-
-    when:
-    span.setTag(ANALYTICS_SAMPLE_RATE, rate)
-
-    then:
-    span.metrics == result
-
-    where:
-    rate  | result
-    00    | [(ANALYTICS_SAMPLE_RATE): 0]
-    1     | [(ANALYTICS_SAMPLE_RATE): 1]
-    0f    | [(ANALYTICS_SAMPLE_RATE): 0]
-    1f    | [(ANALYTICS_SAMPLE_RATE): 1]
-    0.1   | [(ANALYTICS_SAMPLE_RATE): 0.1]
-    1.1   | [(ANALYTICS_SAMPLE_RATE): 1.1]
-    -1    | [(ANALYTICS_SAMPLE_RATE): -1]
-    10    | [(ANALYTICS_SAMPLE_RATE): 10]
-    "00"  | [(ANALYTICS_SAMPLE_RATE): 0]
-    "1"   | [(ANALYTICS_SAMPLE_RATE): 1]
-    "1.0" | [(ANALYTICS_SAMPLE_RATE): 1]
-    "0"   | [(ANALYTICS_SAMPLE_RATE): 0]
-    "0.1" | [(ANALYTICS_SAMPLE_RATE): 0.1]
-    "1.1" | [(ANALYTICS_SAMPLE_RATE): 1.1]
-    "-1"  | [(ANALYTICS_SAMPLE_RATE): -1]
-    "str" | [:]
-  }
-
-  def "set priority sampling via tag"() {
-    when:
-    span.setTag(tag, value)
-
-    then:
-    span.samplingPriority == expected
-
-    where:
-    tag                | value   | expected
-    DDTags.MANUAL_KEEP | true    | PrioritySampling.USER_KEEP
-    DDTags.MANUAL_KEEP | false   | null
-    DDTags.MANUAL_KEEP | "true"  | PrioritySampling.USER_KEEP
-    DDTags.MANUAL_KEEP | "false" | null
-    DDTags.MANUAL_KEEP | "asdf"  | null
-
-    DDTags.MANUAL_DROP | true    | PrioritySampling.USER_DROP
-    DDTags.MANUAL_DROP | false   | null
-    DDTags.MANUAL_DROP | "true"  | PrioritySampling.USER_DROP
-    DDTags.MANUAL_DROP | "false" | null
-    DDTags.MANUAL_DROP | "asdf"  | null
-  }
-
   def "DBStatementAsResource should not interact on Mongo queries"() {
     when:
     span.setResourceName("not-change-me")

dd-trace-ot/src/test/groovy/datadog/opentracing/decorators/URLAsResourceNameTest.groovy

@@ -3,7 +3,6 @@ package datadog.opentracing.decorators
 import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.tag.Tags
@@ -113,7 +112,6 @@ class URLAsResourceNameTest extends DDSpecification {
         "fakeService",
         "fakeOperation",
         "fakeResource",
-        PrioritySampling.UNSET,
         null,
         Collections.<String, String> emptyMap(),
         false,

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/B3HttpExtractorTest.groovy

@@ -1,12 +1,10 @@
 package datadog.opentracing.propagation
 
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.SpanContext
 import io.opentracing.propagation.TextMapExtractAdapter
 
 import static datadog.opentracing.DDTracer.TRACE_ID_MAX
-import static datadog.opentracing.propagation.B3HttpCodec.SAMPLING_PRIORITY_KEY
 import static datadog.opentracing.propagation.B3HttpCodec.SPAN_ID_KEY
 import static datadog.opentracing.propagation.B3HttpCodec.TRACE_ID_KEY
 
@@ -22,10 +20,6 @@ class B3HttpExtractorTest extends DDSpecification {
       SOME_HEADER                 : "my-interesting-info",
     ]
 
-    if (samplingPriority != null) {
-      headers.put(SAMPLING_PRIORITY_KEY, "$samplingPriority".toString())
-    }
-
     when:
     final ExtractedContext context = extractor.extract(new TextMapExtractAdapter(headers))
 
@@ -34,16 +28,13 @@ class B3HttpExtractorTest extends DDSpecification {
     context.spanId == spanId
     context.baggage == [:]
     context.tags == ["some-tag": "my-interesting-info"]
-    context.samplingPriority == expectedSamplingPriority
     context.origin == null
 
     where:
-    traceId          | spanId           | samplingPriority | expectedSamplingPriority
+    traceId          | spanId
-    1G               | 2G               | null             | PrioritySampling.UNSET
+    1G               | 2G
-    2G               | 3G               | 1                | PrioritySampling.SAMPLER_KEEP
+    TRACE_ID_MAX     | TRACE_ID_MAX - 1
-    3G               | 4G               | 0                | PrioritySampling.SAMPLER_DROP
+    TRACE_ID_MAX - 1 | TRACE_ID_MAX
-    TRACE_ID_MAX     | TRACE_ID_MAX - 1 | 0                | PrioritySampling.SAMPLER_DROP
-    TRACE_ID_MAX - 1 | TRACE_ID_MAX     | 1                | PrioritySampling.SAMPLER_KEEP
   }
 
   def "extract 128 bit id truncates id to 64 bit"() {

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/B3HttpInjectorTest.groovy

@@ -3,13 +3,11 @@ package datadog.opentracing.propagation
 import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.propagation.TextMapInjectAdapter
 
 import static datadog.opentracing.DDTracer.TRACE_ID_MAX
-import static datadog.opentracing.propagation.B3HttpCodec.SAMPLING_PRIORITY_KEY
 import static datadog.opentracing.propagation.B3HttpCodec.SPAN_ID_KEY
 import static datadog.opentracing.propagation.B3HttpCodec.TRACE_ID_KEY
 
@@ -29,7 +27,6 @@ class B3HttpInjectorTest extends DDSpecification {
         "fakeService",
         "fakeOperation",
         "fakeResource",
-        samplingPriority,
         "fakeOrigin",
         new HashMap<String, String>() {
           {
@@ -51,19 +48,12 @@ class B3HttpInjectorTest extends DDSpecification {
     then:
     1 * carrier.put(TRACE_ID_KEY, traceId.toString(16).toLowerCase())
     1 * carrier.put(SPAN_ID_KEY, spanId.toString(16).toLowerCase())
-    if (expectedSamplingPriority != null) {
-      1 * carrier.put(SAMPLING_PRIORITY_KEY, "$expectedSamplingPriority")
-    }
     0 * _
 
     where:
-    traceId          | spanId           | samplingPriority              | expectedSamplingPriority
+    traceId          | spanId
-    1G               | 2G               | PrioritySampling.UNSET        | null
+    1G               | 2G
-    2G               | 3G               | PrioritySampling.SAMPLER_KEEP | 1
+    TRACE_ID_MAX     | TRACE_ID_MAX - 1
-    4G               | 5G               | PrioritySampling.SAMPLER_DROP | 0
+    TRACE_ID_MAX - 1 | TRACE_ID_MAX
-    5G               | 6G               | PrioritySampling.USER_KEEP    | 1
-    6G               | 7G               | PrioritySampling.USER_DROP    | 0
-    TRACE_ID_MAX     | TRACE_ID_MAX - 1 | PrioritySampling.UNSET        | null
-    TRACE_ID_MAX - 1 | TRACE_ID_MAX     | PrioritySampling.SAMPLER_KEEP | 1
   }
 }

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/DatadogHttpExtractorTest.groovy

@@ -1,6 +1,5 @@
 package datadog.opentracing.propagation
 
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.SpanContext
 import io.opentracing.propagation.TextMapExtractAdapter
@@ -8,7 +7,6 @@ import io.opentracing.propagation.TextMapExtractAdapter
 import static datadog.opentracing.DDTracer.TRACE_ID_MAX
 import static datadog.opentracing.propagation.DatadogHttpCodec.ORIGIN_KEY
 import static datadog.opentracing.propagation.DatadogHttpCodec.OT_BAGGAGE_PREFIX
-import static datadog.opentracing.propagation.DatadogHttpCodec.SAMPLING_PRIORITY_KEY
 import static datadog.opentracing.propagation.DatadogHttpCodec.SPAN_ID_KEY
 import static datadog.opentracing.propagation.DatadogHttpCodec.TRACE_ID_KEY
 
@@ -26,10 +24,6 @@ class DatadogHttpExtractorTest extends DDSpecification {
       SOME_HEADER                             : "my-interesting-info",
     ]
 
-    if (samplingPriority != PrioritySampling.UNSET) {
-      headers.put(SAMPLING_PRIORITY_KEY, "$samplingPriority".toString())
-    }
-
     if (origin) {
       headers.put(ORIGIN_KEY, origin)
     }
@@ -42,15 +36,14 @@ class DatadogHttpExtractorTest extends DDSpecification {
     context.spanId == new BigInteger(spanId)
     context.baggage == ["k1": "v1", "k2": "v2"]
     context.tags == ["some-tag": "my-interesting-info"]
-    context.samplingPriority == samplingPriority
     context.origin == origin
 
     where:
-    traceId                       | spanId                        | samplingPriority              | origin
+    traceId                       | spanId                        | origin
-    "1"                           | "2"                           | PrioritySampling.UNSET        | null
+    "1"                           | "2"                           | null
-    "2"                           | "3"                           | PrioritySampling.SAMPLER_KEEP | "saipan"
+    "2"                           | "3"                           | "saipan"
-    TRACE_ID_MAX.toString()       | (TRACE_ID_MAX - 1).toString() | PrioritySampling.UNSET        | "saipan"
+    TRACE_ID_MAX.toString()       | (TRACE_ID_MAX - 1).toString() | "saipan"
-    (TRACE_ID_MAX - 1).toString() | TRACE_ID_MAX.toString()       | PrioritySampling.SAMPLER_KEEP | "saipan"
+    (TRACE_ID_MAX - 1).toString() | TRACE_ID_MAX.toString()       | "saipan"
   }
 
   def "extract header tags with no propagation"() {

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/DatadogHttpInjectorTest.groovy

@@ -3,7 +3,6 @@ package datadog.opentracing.propagation
 import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.propagation.TextMapInjectAdapter
@@ -11,7 +10,6 @@ import io.opentracing.propagation.TextMapInjectAdapter
 import static datadog.opentracing.DDTracer.TRACE_ID_MAX
 import static datadog.opentracing.propagation.DatadogHttpCodec.ORIGIN_KEY
 import static datadog.opentracing.propagation.DatadogHttpCodec.OT_BAGGAGE_PREFIX
-import static datadog.opentracing.propagation.DatadogHttpCodec.SAMPLING_PRIORITY_KEY
 import static datadog.opentracing.propagation.DatadogHttpCodec.SPAN_ID_KEY
 import static datadog.opentracing.propagation.DatadogHttpCodec.TRACE_ID_KEY
 
@@ -31,7 +29,6 @@ class DatadogHttpInjectorTest extends DDSpecification {
         "fakeService",
         "fakeOperation",
         "fakeResource",
-        samplingPriority,
         origin,
         new HashMap<String, String>() {
           {
@@ -55,19 +52,16 @@ class DatadogHttpInjectorTest extends DDSpecification {
     1 * carrier.put(SPAN_ID_KEY, spanId.toString())
     1 * carrier.put(OT_BAGGAGE_PREFIX + "k1", "v1")
     1 * carrier.put(OT_BAGGAGE_PREFIX + "k2", "v2")
-    if (samplingPriority != PrioritySampling.UNSET) {
-      1 * carrier.put(SAMPLING_PRIORITY_KEY, "$samplingPriority")
-    }
     if (origin) {
       1 * carrier.put(ORIGIN_KEY, origin)
     }
     0 * _
 
     where:
-    traceId          | spanId           | samplingPriority              | origin
+    traceId          | spanId           | origin
-    1G               | 2G               | PrioritySampling.UNSET        | null
+    1G               | 2G               | null
-    1G               | 2G               | PrioritySampling.SAMPLER_KEEP | "saipan"
+    1G               | 2G               | "saipan"
-    TRACE_ID_MAX     | TRACE_ID_MAX - 1 | PrioritySampling.UNSET        | "saipan"
+    TRACE_ID_MAX     | TRACE_ID_MAX - 1 | "saipan"
-    TRACE_ID_MAX - 1 | TRACE_ID_MAX     | PrioritySampling.SAMPLER_KEEP | null
+    TRACE_ID_MAX - 1 | TRACE_ID_MAX     | null
   }
 }

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/HaystackHttpExtractorTest.groovy

@@ -1,6 +1,5 @@
 package datadog.opentracing.propagation
 
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.SpanContext
 import io.opentracing.propagation.TextMapExtractAdapter
@@ -32,15 +31,13 @@ class HaystackHttpExtractorTest extends DDSpecification {
     context.spanId == new BigInteger(spanId)
     context.baggage == ["k1": "v1", "k2": "v2"]
     context.tags == ["some-tag": "my-interesting-info"]
-    context.samplingPriority == samplingPriority
     context.origin == origin
 
     where:
-    traceId                       | spanId                        | samplingPriority              | origin
+    traceId                       | spanId                        | origin
-    "1"                           | "2"                           | PrioritySampling.SAMPLER_KEEP | null
+    "1"                           | "2"                           | null
-    "2"                           | "3"                           | PrioritySampling.SAMPLER_KEEP | null
+    TRACE_ID_MAX.toString()       | (TRACE_ID_MAX - 1).toString() | null
-    TRACE_ID_MAX.toString()       | (TRACE_ID_MAX - 1).toString() | PrioritySampling.SAMPLER_KEEP | null
+    (TRACE_ID_MAX - 1).toString() | TRACE_ID_MAX.toString()       | null
-    (TRACE_ID_MAX - 1).toString() | TRACE_ID_MAX.toString()       | PrioritySampling.SAMPLER_KEEP | null
   }
 
   def "extract header tags with no propagation"() {

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/HaystackHttpInjectorTest.groovy

@@ -3,15 +3,12 @@ package datadog.opentracing.propagation
 import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.propagation.TextMapInjectAdapter
 
 import static datadog.opentracing.DDTracer.TRACE_ID_MAX
-import static datadog.opentracing.propagation.HaystackHttpCodec.OT_BAGGAGE_PREFIX
+import static datadog.opentracing.propagation.HaystackHttpCodec.*
-import static datadog.opentracing.propagation.HaystackHttpCodec.SPAN_ID_KEY
-import static datadog.opentracing.propagation.HaystackHttpCodec.TRACE_ID_KEY
 
 class HaystackHttpInjectorTest extends DDSpecification {
 
@@ -29,7 +26,6 @@ class HaystackHttpInjectorTest extends DDSpecification {
         "fakeService",
         "fakeOperation",
         "fakeResource",
-        samplingPriority,
         origin,
         new HashMap<String, String>() {
           {
@@ -56,10 +52,9 @@ class HaystackHttpInjectorTest extends DDSpecification {
 
 
     where:
-    traceId          | spanId           | samplingPriority              | origin
+    traceId          | spanId           | origin
-    1G               | 2G               | PrioritySampling.SAMPLER_KEEP | null
+    1G               | 2G               | null
-    1G               | 2G               | PrioritySampling.SAMPLER_KEEP | null
+    TRACE_ID_MAX     | TRACE_ID_MAX - 1 | null
-    TRACE_ID_MAX     | TRACE_ID_MAX - 1 | PrioritySampling.SAMPLER_KEEP | null
+    TRACE_ID_MAX - 1 | TRACE_ID_MAX     | null
-    TRACE_ID_MAX - 1 | TRACE_ID_MAX     | PrioritySampling.SAMPLER_KEEP | null
   }
 }

dd-trace-ot/src/test/groovy/datadog/opentracing/propagation/HttpInjectorTest.groovy

@@ -4,7 +4,6 @@ import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
 import datadog.trace.api.Config
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
 import io.opentracing.propagation.TextMapInjectAdapter
@@ -34,7 +33,6 @@ class HttpInjectorTest extends DDSpecification {
         "fakeService",
         "fakeOperation",
         "fakeResource",
-        samplingPriority,
         origin,
         new HashMap<String, String>() {
           {
@@ -59,9 +57,6 @@ class HttpInjectorTest extends DDSpecification {
       1 * carrier.put(DatadogHttpCodec.SPAN_ID_KEY, spanId.toString())
       1 * carrier.put(DatadogHttpCodec.OT_BAGGAGE_PREFIX + "k1", "v1")
       1 * carrier.put(DatadogHttpCodec.OT_BAGGAGE_PREFIX + "k2", "v2")
-      if (samplingPriority != PrioritySampling.UNSET) {
-        1 * carrier.put(DatadogHttpCodec.SAMPLING_PRIORITY_KEY, "$samplingPriority")
-      }
       if (origin) {
         1 * carrier.put(DatadogHttpCodec.ORIGIN_KEY, origin)
       }
@@ -69,20 +64,17 @@ class HttpInjectorTest extends DDSpecification {
     if (styles.contains(B3)) {
       1 * carrier.put(B3HttpCodec.TRACE_ID_KEY, traceId.toString())
       1 * carrier.put(B3HttpCodec.SPAN_ID_KEY, spanId.toString())
-      if (samplingPriority != PrioritySampling.UNSET) {
-        1 * carrier.put(B3HttpCodec.SAMPLING_PRIORITY_KEY, "1")
-      }
     }
     0 * _
 
     where:
-    styles        | samplingPriority              | origin
+    styles        | origin
-    [DATADOG, B3] | PrioritySampling.UNSET        | null
+    [DATADOG, B3] | null
-    [DATADOG, B3] | PrioritySampling.SAMPLER_KEEP | "saipan"
+    [DATADOG, B3] | "saipan"
-    [DATADOG]     | PrioritySampling.UNSET        | null
+    [DATADOG]     | null
-    [DATADOG]     | PrioritySampling.SAMPLER_KEEP | "saipan"
+    [DATADOG]     | "saipan"
-    [B3]          | PrioritySampling.UNSET        | null
+    [B3]          | null
-    [B3]          | PrioritySampling.SAMPLER_KEEP | "saipan"
+    [B3]          | "saipan"
-    [B3, DATADOG] | PrioritySampling.SAMPLER_KEEP | "saipan"
+    [B3, DATADOG] | "saipan"
   }
 }

dd-trace-ot/src/test/groovy/datadog/trace/DDTracerTest.groovy

@@ -3,8 +3,6 @@ package datadog.trace
 import datadog.opentracing.DDTracer
 import datadog.opentracing.propagation.HttpCodec
 import datadog.trace.api.Config
-import datadog.trace.common.sampling.AllSampler
-import datadog.trace.common.sampling.RateByServiceSampler
 import datadog.trace.common.writer.DDAgentWriter
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.common.writer.LoggingWriter
@@ -18,7 +16,6 @@ import static datadog.trace.api.Config.HEADER_TAGS
 import static datadog.trace.api.Config.HEALTH_METRICS_ENABLED
 import static datadog.trace.api.Config.HEALTH_METRICS_STATSD_PORT
 import static datadog.trace.api.Config.PREFIX
-import static datadog.trace.api.Config.PRIORITY_SAMPLING
 import static datadog.trace.api.Config.SERVICE_MAPPING
 import static datadog.trace.api.Config.SPAN_TAGS
 import static datadog.trace.api.Config.WRITER_TYPE
@@ -46,11 +43,10 @@ class DDTracerTest extends DDSpecification {
 
     then:
     tracer.serviceName == "unnamed-java-app"
-    tracer.sampler instanceof RateByServiceSampler
     tracer.writer.toString() == "DDAgentWriter { api=DDApi { tracesUrl=http://localhost:8126/v0.3/traces } }"
     tracer.writer.monitor instanceof DDAgentWriter.NoopMonitor
 
-    tracer.spanContextDecorators.size() == 15
+    tracer.spanContextDecorators.size() == 12
 
     tracer.injector instanceof HttpCodec.CompoundInjector
     tracer.extractor instanceof HttpCodec.CompoundExtractor
@@ -70,15 +66,6 @@ class DDTracerTest extends DDSpecification {
   }
 
 
-  def "verify overriding sampler"() {
-    setup:
-    System.setProperty(PREFIX + PRIORITY_SAMPLING, "false")
-    when:
-    def tracer = new DDTracer(new Config())
-    then:
-    tracer.sampler instanceof AllSampler
-  }
-
   def "verify overriding writer"() {
     setup:
     System.setProperty(PREFIX + WRITER_TYPE, "LoggingWriter")
@@ -131,40 +118,23 @@ class DDTracerTest extends DDSpecification {
     "writer" | "trace.agent.port" | "9999"          | "DDAgentWriter { api=DDApi { tracesUrl=http://localhost:9999/v0.3/traces } }"
   }
 
-  def "verify sampler/writer constructor"() {
+  def "verify writer constructor"() {
     setup:
     def writer = new ListWriter()
-    def sampler = new RateByServiceSampler()
 
     when:
-    def tracer = new DDTracer(DEFAULT_SERVICE_NAME, writer, sampler)
+    def tracer = new DDTracer(DEFAULT_SERVICE_NAME, writer)
 
     then:
     tracer.serviceName == DEFAULT_SERVICE_NAME
-    tracer.sampler == sampler
     tracer.writer == writer
     tracer.localRootSpanTags[Config.RUNTIME_ID_TAG].size() > 0 // not null or empty
     tracer.localRootSpanTags[Config.LANGUAGE_TAG_KEY] == Config.LANGUAGE_TAG_VALUE
   }
 
-  def "Shares TraceCount with DDApi with #key = #value"() {
-    setup:
-    System.setProperty(PREFIX + key, value)
-    final DDTracer tracer = new DDTracer(new Config())
-
-    expect:
-    tracer.writer instanceof DDAgentWriter
-    tracer.writer.traceCount.is(((DDAgentWriter) tracer.writer).traceCount)
-
-    where:
-    key               | value
-    PRIORITY_SAMPLING | "true"
-    PRIORITY_SAMPLING | "false"
-  }
-
   def "root tags are applied only to root spans"() {
     setup:
-    def tracer = new DDTracer('my_service', new ListWriter(), new AllSampler(), '', ['only_root': 'value'], [:], [:], [:])
+    def tracer = new DDTracer('my_service', new ListWriter(), '', ['only_root': 'value'], [:], [:], [:])
     def root = tracer.buildSpan('my_root').start()
     def child = tracer.buildSpan('my_child').asChildOf(root).start()
 

dd-trace-ot/src/test/groovy/datadog/trace/api/sampling/AllSamplerTest.groovy

@@ -1,42 +0,0 @@
-package datadog.trace.api.sampling
-
-import datadog.opentracing.DDSpan
-import datadog.trace.common.sampling.AllSampler
-import datadog.trace.util.test.DDSpecification
-import spock.lang.Subject
-
-import java.util.regex.Pattern
-
-class AllSamplerTest extends DDSpecification {
-
-  @Subject
-  DDSpan span = Mock()
-
-  private final AllSampler sampler = new AllSampler()
-
-  def "test AllSampler"() {
-    expect:
-    for (int i = 0; i < 500; i++) {
-      assert sampler.doSample(span)
-    }
-  }
-
-  def "test skip tag sampler"() {
-    setup:
-    final Map<String, Object> tags = new HashMap<>()
-    2 * span.getTags() >> tags
-    sampler.addSkipTagPattern("http.url", Pattern.compile(".*/hello"))
-
-    when:
-    tags.put("http.url", "http://a/hello")
-
-    then:
-    !sampler.sample(span)
-
-    when:
-    tags.put("http.url", "http://a/hello2")
-
-    then:
-    sampler.sample(span)
-  }
-}

dd-trace-ot/src/test/groovy/datadog/trace/api/sampling/RateByServiceSamplerTest.groovy

@@ -1,71 +0,0 @@
-package datadog.trace.api.sampling
-
-import com.fasterxml.jackson.databind.ObjectMapper
-import datadog.opentracing.DDSpan
-import datadog.opentracing.SpanFactory
-import datadog.trace.common.sampling.RateByServiceSampler
-import datadog.trace.util.test.DDSpecification
-
-import static datadog.trace.common.sampling.RateByServiceSampler.DEFAULT_KEY
-
-class RateByServiceSamplerTest extends DDSpecification {
-
-  def "invalid rate -> 1"() {
-    setup:
-    RateByServiceSampler serviceSampler = new RateByServiceSampler()
-    ObjectMapper serializer = new ObjectMapper()
-    String response = '{"rate_by_service": {"service:,env:":' + rate + '}}'
-    serviceSampler.onResponse("traces", serializer.readTree(response))
-    expect:
-    serviceSampler.serviceRates[DEFAULT_KEY].sampleRate == expectedRate
-
-    where:
-    rate | expectedRate
-    null | 1
-    1    | 1
-    0    | 0.0
-    -5   | 1
-    5    | 1
-    0.5  | 0.5
-  }
-
-  def "rate by service name"() {
-    setup:
-    RateByServiceSampler serviceSampler = new RateByServiceSampler()
-    ObjectMapper serializer = new ObjectMapper()
-
-    when:
-    String response = '{"rate_by_service": {"service:spock,env:test":0.0}}'
-    serviceSampler.onResponse("traces", serializer.readTree(response))
-    DDSpan span1 = SpanFactory.newSpanOf("foo", "bar")
-    serviceSampler.initializeSamplingPriority(span1)
-    then:
-    span1.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
-    serviceSampler.sample(span1)
-
-    when:
-    response = '{"rate_by_service": {"service:spock,env:test":1.0}}'
-    serviceSampler.onResponse("traces", serializer.readTree(response))
-    DDSpan span2 = SpanFactory.newSpanOf("spock", "test")
-    serviceSampler.initializeSamplingPriority(span2)
-    then:
-    span2.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
-    serviceSampler.sample(span2)
-  }
-
-  def "sampling priority set on context"() {
-    setup:
-    RateByServiceSampler serviceSampler = new RateByServiceSampler()
-    ObjectMapper serializer = new ObjectMapper()
-    String response = '{"rate_by_service": {"service:,env:":1.0}}'
-    serviceSampler.onResponse("traces", serializer.readTree(response))
-
-    DDSpan span = SpanFactory.newSpanOf("foo", "bar")
-    serviceSampler.initializeSamplingPriority(span)
-    expect:
-    // sets correctly on root span
-    span.getSamplingPriority() == PrioritySampling.SAMPLER_KEEP
-    // RateByServiceSamler must not set the sample rate
-    span.getMetrics().get("_sample_rate") == null
-  }
-}

dd-trace-ot/src/test/groovy/datadog/trace/api/writer/DDAgentWriterTest.groovy

@@ -5,7 +5,6 @@ import datadog.opentracing.DDSpan
 import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.DDAgentWriter
 import datadog.trace.common.writer.DDApi
 import datadog.trace.util.test.DDSpecification
@@ -167,7 +166,6 @@ class DDAgentWriterTest extends DDSpecification {
       "",
       "",
       "",
-      PrioritySampling.UNSET,
       "",
       Collections.emptyMap(),
       false,
@@ -205,7 +203,6 @@ class DDAgentWriterTest extends DDSpecification {
       "",
       "",
       "",
-      PrioritySampling.UNSET,
       "",
       Collections.emptyMap(),
       false,

dd-trace-ot/src/traceAgentTest/groovy/DDApiIntegrationTest.groovy

@@ -3,7 +3,6 @@ import datadog.opentracing.DDSpan
 import datadog.opentracing.DDSpanContext
 import datadog.opentracing.DDTracer
 import datadog.opentracing.PendingTrace
-import datadog.trace.api.sampling.PrioritySampling
 import datadog.trace.common.writer.DDApi
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.util.test.DDSpecification
@@ -30,7 +29,6 @@ class DDApiIntegrationTest {
       "fakeService",
       "fakeOperation",
       "fakeResource",
-      PrioritySampling.UNSET,
       null,
       Collections.emptyMap(),
       false,