More changes as part of the dualstack design:
- Change resolver and LB policy APIs to support multiple addresses per
endpoint. Specifically, replace `ServerAddress` with
`EndpointAddresses`, which encodes more than one address. Per-address
channel args are retained at the same level, so they are now
per-endpoint. For now, `EndpointAddress` provides a single-address ctor
and a single-address accessor for backward compatibility, so
`ServerAdress` is an alias for `EndpointAddresses`; eventually, this
alias and the single-address methods will be removed.
- Add an `EndpointAddressSet` class, which represents an unordered set
of addresses to be used as a map key. This will be used in a number of
LB policies that need to store per-endpoint state.
- Change the LB policy API's `ChannelControlHelper::CreateSubchannel()`
method to take the address and per-endpoint channel args as separate
parameters, so that we don't need to construct a legacy `ServerAddress`
object as we create a new subchannel for each address in the endpoint.
- Change pick_first to flatten the address list.
- Change ring_hash to use `EndpointAddressSet` as the key for its
endpoint map, and to use the first address of the endpoint as the hash
key.
- Change WRR to use `EndpointAddressSet` as the key for its endpoint
weight map.
Note that support for multiple addresses per endpoint is guarded in RR
by the existing `round_robin_delegate_to_pick_fist` experiment and in
WRR by the existing `wrr_delegate_to_pick_first` experiment.
This PR does *not* include support for multiple addresses per endpoint
for the outlier_detection or xds_override_host LB policies; those will
come in subsequent PRs.
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Co-authored-by: ctiller <ctiller@users.noreply.github.com>
This is a big rewrite of global config.
It does a few things, all somewhat intertwined:
1. centralize the list of configuration we have to a yaml file that can
be parsed, and code generated from it
2. add an initialization and a reset stage so that config vars can be
centrally accessed very quickly without the need for caching them
3. makes the syntax more C++ like (less macros!)
4. (optionally) adds absl flags to the OSS build
This first round of changes is intended to keep the system where it is
without major changes. We pick up absl flags to match internal code and
remove one point of deviation - but importantly continue to read from
the environment variables. In doing so we don't force absl flags on our
customers - it's possible to configure grpc without the flags - but
instead allow users that do use absl flags to configure grpc using that
mechanism. Importantly this lets internal customers configure grpc the
same everywhere.
Future changes along this path will be two-fold:
1. Move documentation generation into the code generation step, so that
within the source of truth yaml file we can find all documentation and
data about a configuration knob - eliminating the chance of forgetting
to document something in all the right places.
2. Provide fuzzing over configurations. Currently most config variables
get stashed in static constants across the codebase. To fuzz over these
we'd need a way to reset those cached values between fuzzing rounds,
something that is terrifically difficult right now, but with these
changes should simply be a reset on `ConfigVars`.
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---------
Co-authored-by: ctiller <ctiller@users.noreply.github.com>
There was a ~1% flake in grpclb end2end tests that was reproducible in opt builds, manifesting as a hang, usually in a the SingleBalancerTest.Fallback test. Through experimentation, I found that by skipping the death test in the grpclb end2end test suite, the hang was no longer reproducible in 10,000 runs. Similarly, moving this test to the end of the suite, or making it run first (as is the case in this PR) resulted in 0 failures in 3000 runs.
It's unclear to me yet why the death test causes things to be unstable in this way. It's clear from the logs that one test does affect the rest, grpc_init is done once for all tests, so all tests utilize the same EventEngine ... until the death test completes, and a new EventEngine is created for the next test.
I think this death test is sufficiently artificial that it's fine to change the test ordering itself, and ignore the wonky intermediate state that results from it.
Reproducing the flake:
```
tools/bazel --bazelrc=tools/remote_build/linux.bazelrc test \
-c opt \
--test_env=GRPC_TRACE=event_engine \
--runs_per_test=5000 \
--test_output=summary \
test/cpp/end2end/grpclb_end2end_test@poller=epoll1
```
* Add a provision to allow specification of separate set of channel args for the grpclb channel
* fix asan issue
* review comments
* review comments
* add missing file
* remove unused hdr
* fix sanity
* fix comments
* remove unused hdr
* service config API: use absl::Status instead of grpc_error
* Automated change: Fix sanity tests
* add missing build deps
* attempt to work around build breakage on older compilers
* trying the work-around in more spots
* more work-arounds
* more workarounds
* Automated change: Fix sanity tests
* work around another compiler problem
* Automated change: Fix sanity tests
* Automated change: Fix sanity tests
Co-authored-by: markdroth <markdroth@users.noreply.github.com>
* Refactor end2end tests to exercise each EventEngine
* fix incorrect bazel_only exclusions
* Automated change: Fix sanity tests
* microbenchmark fix
* sanitize, fix iOS flub
* Automated change: Fix sanity tests
* iOS fix
* reviewer feedback
* first pass at excluding EventEngine test expansion
Also caught a few cases where we should not test pollers, but should
test all engines. And two cases where we likely shouldn't be testing
either product.
* end2end fuzzers to be fuzzed differently via EventEngine.
* sanitize
* reviewer feedback
* remove misleading comment
* reviewer feedback: comments
* EE test_init needs to play with our build system
* fix golden file test runner
Co-authored-by: drfloob <drfloob@users.noreply.github.com>
Based on a handful of https://abseil.io/tips, it's generally advised to
only fully-qualify namespaces when in a `using` statement, or when it's
otherwise required for compilation. In all other cases, the general
recommendation is to not fully-qualify.
This change fixes most `grpc.*` namespace uses. There are potential
challenges in trying to make blanket changes to non-gRPC namespace uses,
such as `::testing`, since there is also a `grpc::testing` namespace.
Based on a handful of https://abseil.io/tips, it's generally advised to
only fully-qualify namespaces when in a `using` statement, or when it's
otherwise required for compilation. In all other cases, the general
recommendation is to not fully-qualify.
This change fixes most `grpc.*` namespace uses. There are potential
challenges in trying to make blanket changes to non-gRPC namespace uses,
such as `::testing`, since there is also a `grpc::testing` namespace.
This temporarily unblocks a related gtest upgrade. The ultimate goal is
to upgraade our gtest dependencies, but I don't have the cycles to
manage a potentially messy migration until at least next week. This PR
is coordinated with an internal change.
It is not possible for such a function to be implemented in a way that
is understood by annotalysis. Mark it deprecated and replace instances
of its use with direct mutex/condvar usage.
Add a bunch of missing thread safety annotations while I'm here.
Mark D. Roth
Craig Tiller
Jan Tattermusch
AJ Heller
Cheng-Yu Chung
Esun Kim
Vignesh Babu
yihuaz
Yash Tibrewal
Tamir Duberstein