runtime/pprof: flaky TestGenericsHashKeyInPprofBuilder

[prattmic]

#!watchflakes
default <- pkg == "runtime/pprof" && test == "TestGenericsHashKeyInPprofBuilder"

This test failed in CI: https://ci.chromium.org/ui/p/golang/builders/try/gotip-linux-amd64-staticlockranking/b8732088109106960193/test-results?sortby=&groupby=

The problem is we got

testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint32] [1 128 1 128]

but want

testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint32] [1 128 0 0]

I think this is saying that the allocation is unexpectedly live. The 128 one at https://cs.opensource.google/go/go/+/master:src/runtime/pprof/protomem_test.go;l=132;drc=6f59c11155d75024985d4827a7fe155cd6561df9.

This test isn't intending to test liveness at all, so ignoring that field likely makes the most sense.

cc @golang/runtime

[gabyhelp]

Related Issues and Documentation

• runtime/pprof: TestProfilerStackDepth/heap failures #70112 (closed)
• runtime/pprof: TestBlockMutexProfileInlineExpansion/block failures [consistent failure] #69764 (closed)
• runtime/pprof: TestMutexProfile failures #62094
• runtime/pprof: TestBlockMutexProfileInlineExpansion/mutex failures #69765 (closed)
• runtime/pprof: incorrect function names for generics functions #64528 (closed)
• runtime/pprof: TestGoroutineProfileConcurrency failures with `profile includes finalizer` #56875
• runtime/pprof: TestProfilerStackDepth/mutex failures #68562 (closed)
• runtime/pprof: TestGoroutineProfileConcurrency/finalizer_present failures #68456 (closed)
• runtime/pprof: test timed out in `StartCPUProfile` #60108 (closed)
• net/http/pprof: TestDeltaProfile failures #61715

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "runtime/pprof" && test == "TestGenericsHashKeyInPprofBuilder"

2024-11-21 10:40 gotip-linux-amd64-staticlockranking go@28f4e14e runtime/pprof.TestGenericsHashKeyInPprofBuilder (log)

=== RUN   TestGenericsHashKeyInPprofBuilder
    protomem_test.go:158: profile = testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.WriteHeapProfile;runtime/pprof.writeHeap;runtime/pprof.writeHeapInternal [0 0 0 0]
        testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;bytes.NewBuffer [0 0 0 0]
        testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint64] [1 64 0 0]
        testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint64] [1 32 0 0]
        testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint32] [1 256 0 0]
        testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint32] [1 128 1 128]
        testing.tRunner;runtime/pprof.TestConvertMemProfile.func1;runtime/pprof.writeHeapProto;runtime/pprof.(*profileBuilder).build;compress/gzip.(*Writer).Write;compress/flate.NewWriter [2 1327104 0 0]
        testing.tRunner;runtime/pprof.TestEmptyStack;runtime/pprof.translateCPUProfile;internal/profile.Parse;compress/gzip.NewReader;compress/gzip.(*Reader).Reset;compress/gzip.(*Reader).readHeader;compress/flate.NewReader [1 4864 0 0]
        testing.tRunner;runtime/pprof.TestEmptyStack;runtime/pprof.translateCPUProfile;runtime/pprof.(*profileBuilder).build;compress/gzip.(*Writer).Write;compress/flate.NewWriter;compress/flate.(*compressor).init [1 262144 0 0]
...
        runtime.systemstack;runtime.newproc.func1;runtime.newproc1;runtime.malg [17 7616 17 7616]
        testing.tRunner;runtime/pprof.TestMemoryProfiler;runtime/pprof.allocateTransient2M [16 256 0 0]
        testing.tRunner;runtime/pprof.TestMemoryProfiler;runtime/pprof.allocateTransient2M [1 128 0 0]
        testing.tRunner;runtime/pprof.TestMemoryProfiler;runtime/pprof.allocateTransient2M [1 2097152 0 0]
        testing.tRunner;runtime/pprof.TestMemoryProfiler;runtime/pprof.allocateTransient1M [1024 1048576 0 0]
        testing.tRunner;runtime/pprof.TestMemoryProfiler [1024 24576 0 0]
        testing.tRunner;runtime/pprof.TestMemoryProfiler [1024 1048576 0 0]
        runtime.mstart;runtime.mstart0;runtime.mstart1;runtime.schedule;runtime.resetspinning;runtime.wakep;runtime.startm;runtime.newm;runtime.allocm [8 16384 8 16384]
        want = testing.tRunner;runtime/pprof.TestGenericsHashKeyInPprofBuilder;runtime/pprof.genericAllocFunc[go.shape.uint32] [1 128 0 0]
--- FAIL: TestGenericsHashKeyInPprofBuilder (1.70s)

— watchflakes