ServerImpl uses that ticker to create incoming Deadlines. This feature is specifically restricted to in-process, as it can also customize ScheduledExecutorService, and them together can fake out the clock which is useful in tests. On the other hand, a fake Ticker won't work with Netty's ScheduledExecutorService.
Also improved mismatch detection, documentation and tests in Deadline.
Fixes#5593 and supersedes #5601
Now that https://github.com/census-instrumentation/opencensus-java/pull/1854 has been merged & released as 0.21.0. We can start using the method & status tags.
Background:
Opencensus introduced new tags for status and method (https://github.com/census-instrumentation/opencensus-java/pull/1115). The old views that used those tags were deprecated and new views were created that used the new tags. However grpc-java wasn't updated to use the new tags due to concern of breaking existing metrics. This resulted in the old views being deprecated while the new views were broken (goomics #50).
https://github.com/census-instrumentation/opencensus-java/pull/1854 added a compatibility layer to opencensus that would remap new tags to old tags for old views. This should unblock grpc to switching to the new tags while allowing old views to still be populated. That commit was released as part of opencensus 0.21, which grpc currently uses
* Bump PerfMark to 0.17.0
The main changes how linking is done. Linking is now always done
through the `PerfMark` entry class. This is for two reasons:
1. It make instrumenting the linking calls *much* easier.
2. It follows the API pattern of "verbNoun()". Previous callsites
would have `Link link = PerfMark.link(); link.link()`. This
stuttering is not quick to follow.
Generated using:
```
find -name \*.java -exec sed -i 's#link = PerfMark.link();#link = PerfMark.linkOut();#g' {} \;
find -name \*.java -exec sed -i 's#link.link();#PerfMark.linkIn(link);#g' {} \;
find -name \*.java -exec sed -i 's#command.getLink().link();#PerfMark.linkIn(command.getLink());#g' {} \;
find -name \*.java -exec sed -i 's#cmd.getLink().link();#PerfMark.linkIn(cmd.getLink());#g' {} \;
find -name \*.java -exec sed -i 's#msg.getLink().link();#PerfMark.linkIn(msg.getLink());#g' {} \;
```
Since the deprecated link methods are also `@DoNotCall`, the same
sed calls will need to be used on import.
Works for #4740
- Subclasses of `AbstractClientStream` include remote address in insight if available.
- `DelayedStream` adds buffered time, and the insight of real stream if it's set.
- `RetriableStream` insights outputs of Substreams.
Example error message:
```
deadline exceeded after 8112071ns. [buffered_nanos=24763, remote_addr=foo.test.google.fr/127.0.0.1:44749]
```
or
```
deadline exceeded after 8112071ns. [buffered_nanos=22344324763, waiting_for_connection]
```
This is related to #4776 but taking a more usage-specific approach.
In #5892 getAttributes() is called without any regard of timing.
Currently DelayedStream.getAttributes() wil throw if called before
passThrough was set. Just to be safe, we are removing that
restriction and making it clear on the javadoc.
On the other hand, we intend to keep the timing restriction on
ClientCall.getAttributes().
This change removes the WriteQueue linking and splits it out into each
of the commands, so that the trace is more precise, and the tag
information is correct.
It is still unclear what the initial Tag should be for ClientCallImpl,
since it should not access the TransportState to get the HTTP/2 stream id.
No more methods on the `LoadBalancer` will be called after
`LoadBalancer#shutdown()` is called. This includes
`LoadBalancer#handleSubchannelState()` too. `SubchannelStateListener`
inherited this restriction. However, this special case makes
`onSubchannelState(SHUTDOWN)` an unreliable way of being notified
about `Subchannel` SHUTDOWN, and may confuse/complicate a
wrapping `LoadBalancer` that expects the full notification (e.g., #5875).
The javadoc isn't clear whether this restriction applies. I think
it's more useful to make it no apply.
We were logging when withDeadline() was used, not when the Context was used. As
discovered while looking at https://stackoverflow.com/q/56593692/4690866 .
In e19e8f7d updateTimeoutHeaders was removed and logIfContextNarrowedTimeout
was called directly. However, the two methods had reverse ordering of
callDeadine/outerCallDeadline and the caller did not get their arguments
swapped.
panic mode was temporarily disabled by #4152 and re-enabled by #4245,
but the tests were not. This has caused a few test code that was
broken but not executed at all.
This add perfmark annotations in some key places, notably on transport/application boundaries, and thread hop locations. Perfmark records to a thread-local buffer the events that happen in each thread. Perfmark is disabled by default, and will compile to a noop unless Perfmark.setEnabled is invoked. This should make it free when disable, and pretty fast when it is enabled.
It is important that started tasks are ended, so several places in our code are moved to either try-finally blocks, or moved into a private method. I realize this is ugly, but I think it is manageable. In the future, we can look at making an agent or compiler plugin that simplifies the recording.
Linking between threads is done with a Link object, which is created on the "outbound" task, and used on the "inbound" task. This is slightly more verbose, and does has a small amount of runtime overhead, even when disabled. (for null checks, slightly higher memory usage, etc.) I think this is okay to, because it makes other optimizations much easier.
Previously, AutoConfiguredLoadBalancer was also handling it, but it
doesn't trigger retries. By returning true for
canHandleEmptyAddressListFromNameResolution(),
AutoConfiguredLoadBalancer effectively by-passed the empty-result
handling logic in ManagedChannelImpl, thus resolution retries were
never triggered.
This change requires AutoConfiguredLoadBalancer to stop being a
LoadBalancer, for its tryHandleResolvedAddresses(). It doesn't
cause any trouble because AutoConfiguredLoadBalancer has become
less and less like a LoadBalancer during the service config changes.
As mentioned in 5188[1], the default used with the enableKeepAlive API
conflicted with the default server enforcement. Instead of fixing it,
remove it. These APIs were deprecated in v1.3.0 in April 2017.
1. https://github.com/grpc/grpc-java/issues/5188#issuecomment-482269303
The `method` and `status` shouldn't be propagated in the first place,
but in previous OpenCensus implementation all tags are propagating by
default. Now with the TagMetadata it may make sense to change them to
local tags.
This will be a breaking change to users who depend on the behavior that
these tags propagate through process boundaries.
The old createSubchannel() doesn't require being called from
sync-context, thus its implementation schedules start() on
sync-context because start() has such requirement. However, if a
LoadBalancer call createSubchannel() in sync-context, start() is
queued and only called after the control exits the sync-context. If
createSubchannel() is immediately followed by other Subchannel methods
that requires start(), such as requestConnection(), they will fail.
This will be a very common issue as most LoadBalancers call
createSubchannel() in the sync-context.
This fix splits out the real work of start() into internalStart() which
is called by the old createSubchannel().
Previously PickResult's Subchannel must be the actual implementation
returned from the Channel's Helper, and Channel would cast it to the
implementation class in order to use it. This will be broken if
Subchannel is wrapped in the case of hierarchical LoadBalancers.
getInternalSubchannel() is the guaranteed path for the Channel to get
the InternalSubchannel implementation. It is friendly for wrapping.
Background: #5676
The pick_first policies in core and grpclb previously would call
Subchannel.requestConnection() from data-path. They now will schedule
that call in the sync-context to avoid the warning. They will only
call it for the first pick of each picker, to prevent storming the
sync-context.
This is a revised version of #5503 (62b03fd), which was rolled back in f8d0868. The newer version passes SubchannelStateListener to Subchannel.start() instead of SubchannelCreationArgs, which allows us to remove the Subchannel argument from the listener, which works as a solution for #5676.
LoadBalancers that call the old createSubchannel() will get start() implicitly called with a listener that passes updates to the deprecated LoadBalancer.handleSubchannelState(). Those who call the new createSubchannel() will have to call start() explicitly.
GRPCLB code is still using the old API, because it's a pain to migrate the SubchannelPool to the new API. Since CachedSubchannelHelper is on the way, it's easier to switch to it when it's ready. Keeping
GRPCLB with the old API would also confirm the backward compatibility.
Contrary to #5736, we will still keep the sync-context requirement of
requestConnection(), because it prevents API fragmentation.
PickFirstLoadBalancer is the only known violator. We will fix it on
master, but we don't want to make that change on 1.21.x because the
release is soon. We simply remove the warning in this release so that
users won't be annoyed.
This supersedes #5736
We will require Subchannel.requestConnection() to be called from
sync-context (#5722), but SubchannelPicker.requestConnection() is
currently calling it with the assumption of thread-safety. Actually
SubchannelPicker.requestConnection() is called already from
sync-context by ChannelImpl, it makes more sense to move this method
to LoadBalancer where all other methods are sync-context'ed, rather than
making SubchannelPicker.requestConnection() sync-context'ed and fragmenting
the SubchannelPicker API because pickSubchannel() is thread-safe.
C++ also has the requestConnection() equivalent on their LoadBalancer
interface.
We check for idle mode the first time we try newStream(), but failed to when
newStream races with reprocess(). This would normally be a very rare race,
except when you consider that AbstractChannelBuilder will call
managedChannel.enterIdle() when the network changes.
Fixes#5729
Dharmesh Jogadia
Chengyuan Zhang
Kun Zhang
Igor Bernstein
ZHANG Dapeng
Jihun Cho
Carl Mastrangelo
Eric Anderson
Ran
Yang Song