f30964ab82
Notably, protobuf to 3.25.8, opentelemetry to 1.52.0. Protobuf in Bazel has 25.5 in the BCR and it seems better to align the WORKSPACE with that version. But we can't actually use 25.5 in BCR because it is incompatible with Bazel 7. |
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|---|---|---|
| .. | ||
| src/main | ||
| README.md | ||
| build.gradle | ||
| pom.xml | ||
| settings.gradle | ||
README.md
gRPC Debug Example
The debug example uses a Hello World style server whose response includes its hostname. It demonstrates usage of the AdminInterface and the grpcdebug commandline tool.
The example requires grpc-java to already be built. You are strongly encouraged to check out a git release tag, since there will already be a build of grpc available. Otherwise, you must follow COMPILING.
Build the example
-
Optional: Build the hello-world-debug example client. See the examples README
-
Build the debuggable server and client. From the
grpc-java/examples/example-debugdirectory run:
$ ../gradlew installDist
This creates the script
build/install/example-debug/bin/hostname-debuggable-server that runs the
example.
To run the debug example, run:
$ ./build/install/example-debug/bin/hostname-debuggable-server
And in a different terminal window run the client.
Note: You can use the standard hello-world client with no debugging enabled and still see results on the server. However, if you want to get debug information about the client you need to run the hello-world-debuggable client.
Simple client
$ ../build/install/examples/bin/hello-world-client
debug enabled client
$ ./build/install/example-debug/bin/hello-world-debuggable-client
Maven
If you prefer to use Maven:
-
Build the hello-world example client. See the examples README
-
Run in this directory:
$ mvn verify
$ # Run the server (from the example-debug directory)
$ mvn exec:java -Dexec.mainClass=io.grpc.examples.debug.HostnameServer
$ # In another terminal run the client (from the examples directory)
$ cd ..
$ mvn exec:java -Dexec.mainClass=io.grpc.examples.helloworld.HelloWorldClient
Using grpcdebug
grpcdebug is a tool that has been created to access the metrics from the channelz and health services.
Installing the grpcdebug tool
The source code is located in a github project grpc-ecosystem/grpcdebug. You can either download [the latest built version] (https://github.com/grpc-ecosystem/grpcdebug/releases/latest) (recommended) or follow the README.md to build it yourself.
Running the grpcdebug tool
Usage
grpcdebug <target address> [flags] channelz <command> [argument]
| Command | Argument | Description |
|---|---|---|
| channel | <channel id or URL> | Display channel states in a human readable way. |
| channels | Lists client channels for the target application. | |
| server | <server ID> | Displays server state in a human readable way. |
| servers | Lists servers in a human readable way. | |
| socket | <socket ID> | Displays socket states in a human readable way. |
| subchannel | <id> | Display subchannel states in human readable way. |
Generally, you will start with either servers or channels and then work down
to the details
Getting overall server info
bin/grpcdebug/grpcdebug localhost:50051 channelz servers
This will show you the server ids with their activity
Server ID Listen Addresses Calls(Started/Succeeded/Failed) Last Call Started
2 [[::]:50051] 38/34/3 now
Getting details for a service
bin/grpcdebug/grpcdebug localhost:50051 channelz server 2
The output will include more communication details and will show socket ids for currently connected clients
Server Id: 2
Listen Addresses: [[::]:50051]
Calls Started: 33
Calls Succeeded: 29
Calls Failed: 3
Last Call Started: now
---
Socket ID Local->Remote Streams(Started/Succeeded/Failed) Messages(Sent/Received)
19 [::1]:50051->[::1]:39834 4/3/0 3/4
Displaying detailed info for a server side connection (socket)
bin/grpcdebug/grpcdebug localhost:50051 channelz socket 19
This will show a lot of gRPC internal information
Socket ID: 19
Address: [::1]:50051->[::1]:50094
Streams Started: 1
Streams Succeeded: 0
Streams Failed: 0
Messages Sent: 0
Messages Received: 1
Keep Alives Sent: 0
Last Local Stream Created:
Last Remote Stream Created: now
Last Message Sent Created:
Last Message Received Created: now
Local Flow Control Window: 65535
Remote Flow Control Window: 1048569
---
Socket Options Name Value
SO_LINGER [type.googleapis.com/grpc.channelz.v1.SocketOptionLinger]:{}
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#TCP_CORK false
WRITE_BUFFER_HIGH_WATER_MARK 65536
WRITE_BUFFER_LOW_WATER_MARK 32768
IP_TOS 0
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#TCP_KEEPCNT 9
SINGLE_EVENTEXECUTOR_PER_GROUP true
SO_SNDBUF 2626560
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#TCP_NOTSENT_LOWAT 0
WRITE_BUFFER_WATER_MARK WriteBufferWaterMark(low: 32768, high: 65536)
TCP_NODELAY true
SO_RCVBUF 131072
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#SO_BUSY_POLL 0
IP_TRANSPARENT false
SO_KEEPALIVE true
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#TCP_QUICKACK false
ALLOCATOR PooledByteBufAllocator(directByDefault: true)
TCP_FASTOPEN_CONNECT false
MESSAGE_SIZE_ESTIMATOR io.grpc.netty.shaded.io.netty.channel.DefaultMessageSizeEstimator@48d475b6
WRITE_SPIN_COUNT 16
SO_REUSEADDR true
CONNECT_TIMEOUT_MILLIS 30000
ALLOW_HALF_CLOSURE false
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#EPOLL_MODE EDGE_TRIGGERED
MAX_MESSAGES_PER_READ 16
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#TCP_KEEPIDLE 7200
AUTO_CLOSE true
io.grpc.netty.shaded.io.netty.channel.epoll.EpollChannelOption#TCP_KEEPINTVL 75
MAX_MESSAGES_PER_WRITE 2147483647
AUTO_READ true
TCP_MD5SIG null
RCVBUF_ALLOCATOR io.grpc.netty.shaded.io.netty.channel.AdaptiveRecvByteBufAllocator@360691a0
Displaying the list of gRPC client channels
Command
bin/grpcdebug/grpcdebug localhost:50051 channelz channels
Output
Channel ID Target State Calls(Started/Succeeded/Failed) Created Time
1 localhost:50051 READY 34/34/0
3 localhost:50051 READY 16/16/0
Note: If you have a simple server that doesn't use gRPC clients to contact other servers, then this table will be empty.
Displaying details of a gRPC client channel
Command
bin/grpcdebug/grpcdebug localhost:50051 channelz channel 3
Output
Channel ID: 3
Target: localhost:50051
State: READY
Calls Started: 16
Calls Succeeded: 16
Calls Failed: 0
Created Time:
---
Subchannel ID Target State Calls(Started/Succeeded/Failed) CreatedTime
10 [[[localhost/127.0.0.1:50051]/{}], [[localhost/0:0 READY 16/16/0
Displaying details of a gRPC client subchannel
Command
bin/grpcdebug/grpcdebug localhost:50051 channelz subchannel 10
Output
Subchannel ID: 10
Target: [[[localhost/127.0.0.1:50051]/{}], [[localhost/0:0:0:0:0:0:0:1:50051]/{}]]
State: READY
Calls Started: 16
Calls Succeeded: 16
Calls Failed: 0
Created Time:
---
Socket ID Local->Remote Streams(Started/Succeeded/Failed) Messages(Sent/Received)
11 127.0.0.1:48536->127.0.0.1:50051 16/16/0 12/12