It is easy to manage these things outside of MultiChildLb and it makes
the shared code easier and use less memory. In particular, we don't want
to use many instances of GracefulSwitchLb in virtually every policy
simply because it was needed in one or two cases.
Adds interfaces required for recording metrics from gRPC components. And added API to get `MetricRecorder` in `LoadBalancer.Helper` and add `MetricSink` to `ManagedChannelBuilder`.
The recommended way to load dependencies from `rules_jvm_external`
is to make use of the `@maven` workspace, and the most readable
way of doing that is to use the `artifact` macro provides.
This removes the need to generate the "compat" namespaces, which
`rules_jvm_external` provided for backwards compatibility with
older releases. This change also sets things up for supporting
`bzlmod`: this requires all workspaces accessed by a library to
be named "up front" in the `MODULE.bazel` file. This way, the
only repo that needs to be exported is `@maven`, rather than the
current huge list.
Including a Status description makes it easier to debug subchannel
closure issues if it's clear that a subchannel became unavailable because
of an outlier detection ejection.
* Allow the queued byte threshold for a Stream to be ready to be configurable
- on clients this is exposed by setting a CallOption
- on servers this is configured by calling a method on ServerCall or ServerStreamListener
* add final, change method permissions, add javadoc, cleanup unneeded, move updateOverallBalancingState to ClusterManagerLB and make it abstract
* Restructure to eliminate the flags as protected methods
* Move methods around so that the candidates for override are near the top.
* Reorder picker methods lower
This change has health checking consumer (new pick first) to install a listener through and health checking producer (outlier detection and client health checking) producing health checks. Health notification chain is built reusing the previous connectivity state chain.
Pickfirst installs the health listener, and is capable of detecting when no health checking producer is installed in the system. In that case, it sets health status to be READY so that health system is no-op.
We already do this for WRR. Notably, we are no longer trying to avoid
the modulus each pick. It was of questionable value, and removing it is
necessary to continue sharing the same integer when the list size
changes.
The change means we can implement a stronger isEquivalentTo() by
comparing the AtomicInteger references. It is strong enough that the
operation aligns with normal equals(). Using equals() instead of
isEquivalentTo() also made more obvious an equals() optimization that
uses the hashCode() before the more expensive HashSet creation; equals()
should now be very fast except when they are (very likely) equal.
An OutlierDetectionLoadBalancer child load balancer might decided to
shut down any subchannel it is tracking. We need to make sure that those
subchannels are removed from the outlier detection tracker map to avoid
a memory leak.
* Update picker logic per A61 that it no longer pays attention to the first 2 elements, but rather takes the first ring element not in TF and uses that.
---------
Pulled in by rebase:
Eric Anderson (android: Remove unneeded proguard rule 44723b6)
Terry Wilson (stub: Deprecate StreamObservers b5434e8)
Instead of a boolean, we now return a Status object. Status.OK
represents accepted addresses and other non-acceptance. This allows the
LB to provide more information about why a set of addresses were not
acceptable.
The status will later be sent to the name resolver as well to allow it
to also better react to to bad addresses.
FixedResultPicker can be used in more situations. Note that
WrrLocalityLoadBalancerTest's test was changed non-trivially. The
noChildLb test was particularly nasty as it assumed
LoadBalancer.ErrorPicker had same toString() as
GracefulSwitchLoadBalancer's ErrorPicker.
* Mark MultiChildLoadBalancer as Internal. Cannot move to the internal package because of its use of classes in the util package.
* Exclude MultiChildLoadBalancer from javadoc generation.
* Fix javadoc creation.
OutlierDetectionLoadBalancer did not delegate calls to an existing
ClientStreamTracer from the tracer it installed. This change has the OD
tracer delegate all calls to the underlying one.
Eric Anderson
Vindhya Ningegowda
David Burns
Terry Wilson
Larry Safran
James Duong
yifeizhuang
Terry Wilson
sanjaypujare