thrift_proxy: refactor thrift router stats to create named stats/stat names once

[fishcakez]

Commit Message: thrift_proxy: refactor thrift router stats to create named stats/stat names once
Additional Description: The Router::RequestOwner constructor is called once per upstream request. The constructor creates stats and adds stat names to symbol tables. These are always the same named counters/histograms and stat names. When using payload passthrough and only the router filter the RequestOwner constructor is 20% +/- 1.5% of the time spent in the ThriftProxy namespace. Therefore refactor the stats out to their own class and create in the filter factory, and pass a constant reference to the router filter and through to other router classes' constructors.

perf flamegraph where Envoy::Extensions::NetworkFilters::ThriftProxy::Rout on the wide left tower is the Router and RequestOwner constructors.

Risk Level: low
Testing: unit tests
Docs Changes: N/A
Release Notes: N/A
Platform Specific Features: N/A

[rgs1]

cc: @jmarantz in case there are other places where we could do this too.

[fishcakez]

Unrelated CI failure:

ERROR: /build/tmp/_bazel_envoybuild/b570b5ccd0454dc9af9f65ab1833764d/external/com_github_lyft_protoc_gen_star/BUILD.bazel:3:11: GoCompilePkg external/com_github_lyft_protoc_gen_star/protoc-gen-star.a [for host] failed: (Exit 1): builder failed: error executing command 
  (cd /build/tmp/_bazel_envoybuild/b570b5ccd0454dc9af9f65ab1833764d/execroot/envoy && \
  exec env - \
    CGO_ENABLED=1 \
    GOARCH=amd64 \
    GOOS=linux \
    GOPATH='' \
    GOROOT=external/go_sdk \
    GOROOT_FINAL=GOROOT \
    PATH=/opt/llvm/bin:/usr/bin:/bin \
  bazel-out/host/bin/external/go_sdk/builder compilepkg -sdk external/go_sdk -installsuffix linux_amd64 -src external/com_github_lyft_protoc_gen_star/artifact.go -src external/com_github_lyft_protoc_gen_star/ast.go -src external/com_github_lyft_protoc_gen_star/build_context.go -src external/com_github_lyft_protoc_gen_star/comment.go -src external/com_github_lyft_protoc_gen_star/debug.go -src external/com_github_lyft_protoc_gen_star/docs.go -src external/com_github_lyft_protoc_gen_star/entity.go -src external/com_github_lyft_protoc_gen_star/enum.go -src external/com_github_lyft_protoc_gen_star/enum_value.go -src external/com_github_lyft_protoc_gen_star/extension.go -src external/com_github_lyft_protoc_gen_star/field.go -src external/com_github_lyft_protoc_gen_star/field_type.go -src external/com_github_lyft_protoc_gen_star/field_type_elem.go -src external/com_github_lyft_protoc_gen_star/file.go -src external/com_github_lyft_protoc_gen_star/generator.go -src external/com_github_lyft_protoc_gen_star/init_option.go -src external/com_github_lyft_protoc_gen_star/message.go -src external/com_github_lyft_protoc_gen_star/method.go -src external/com_github_lyft_protoc_gen_star/module.go -src external/com_github_lyft_protoc_gen_star/name.go -src external/com_github_lyft_protoc_gen_star/node.go -src external/com_github_lyft_protoc_gen_star/oneof.go -src external/com_github_lyft_protoc_gen_star/package.go -src external/com_github_lyft_protoc_gen_star/parameters.go -src external/com_github_lyft_protoc_gen_star/persister.go -src external/com_github_lyft_protoc_gen_star/post_process.go -src external/com_github_lyft_protoc_gen_star/proto.go -src external/com_github_lyft_protoc_gen_star/service.go -src external/com_github_lyft_protoc_gen_star/source_code_info.go -src external/com_github_lyft_protoc_gen_star/wkt.go -src external/com_github_lyft_protoc_gen_star/workflow.go -arc 'github.com/golang/protobuf/proto=github.com/golang/protobuf/proto=bazel-out/host/bin/external/com_github_golang_protobuf/proto/proto.x' -arc 'github.com/golang/protobuf/protoc-gen-go/plugin=github.com/golang/protobuf/protoc-gen-go/plugin=bazel-out/host/bin/external/io_bazel_rules_go/proto/wkt/compiler_plugin_go_proto.x' -arc 'github.com/golang/protobuf/protoc-gen-go/descriptor=github.com/golang/protobuf/protoc-gen-go/descriptor=bazel-out/host/bin/external/io_bazel_rules_go/proto/wkt/descriptor_go_proto.x' -importpath github.com/lyft/protoc-gen-star -p github.com/lyft/protoc-gen-star -package_list bazel-out/host/bin/external/go_sdk/packages.txt -o bazel-out/host/bin/external/com_github_lyft_protoc_gen_star/protoc-gen-star.a -x bazel-out/host/bin/external/com_github_lyft_protoc_gen_star/protoc-gen-star.x -gcflags '' -asmflags '')
Execution platform: @envoy_build_tools//toolchains:rbe_linux_clang_libcxx_platform
compilepkg: missing strict dependencies:
	/b/f/w/external/com_github_lyft_protoc_gen_star/init_option.go: import of "github.com/spf13/afero"
	/b/f/w/external/com_github_lyft_protoc_gen_star/persister.go: import of "github.com/spf13/afero"
No dependencies were provided

[rgs1]

Looks great, thanks! Just one nit about saving an extra const ref when we can just get it from parent, but not blocking on that.

cc: @davinci26 if you are up for another review + merge.

[jmarantz]

Thanks for the heads up, @rgs1 -- this looks like a good refactor. I'm not aware of any that remain at this point, but then I was not aware of this one :)

Probably there is still some low-hanging fruit in other extensions.

[fishcakez]

I merged upstream/main to give CI another go :/

[rgs1]

Over to @davinci26 for merging once CI is happy.

[rgs1]

/assign davinci26