runtime: TestFinalizerInterfaceBig failures

[gopherbot]

#!watchflakes
post <- pkg == "runtime" && test == "TestFinalizerInterfaceBig"

Issue created automatically to collect these failures.

Example (log):

--- FAIL: TestFinalizerInterfaceBig (4.00s)
    mfinal_test.go:115: finalizer for type *bigValue didn't run

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
post <- pkg == "runtime" && test == "TestFinalizerInterfaceBig"

2022-12-08 03:49 windows-amd64-2016 go@b9747e0e runtime.TestFinalizerInterfaceBig (log)

--- FAIL: TestFinalizerInterfaceBig (4.00s)
    mfinal_test.go:115: finalizer for type *bigValue didn't run

— watchflakes

[bcmills]

This test uses an arbitrary timeout and a single GC cycle:

https://cs.opensource.google/go/go/+/master:src/runtime/mfinal_test.go;l=114;drc=58804ea67a28c1d8e37ed548b685bc0c09638886

On a heavily-loaded builder, that could cause it to fail spuriously due to a system scheduler delay.

[bcmills]

Interestingly, this has only failed twice in the past ~2 years — both times recently on Windows.

greplogs -l -e 'FAIL: TestFinalizer' --since=2021-01-01
2022-12-08T03:49:48-b9747e0/windows-amd64-2016
2022-08-08T15:22:02-dd59088/windows-amd64-longtest-newcc

[gopherbot]

Change https://go.dev/cl/456118 mentions this issue: runtime: remove arbitrary timeouts in finalizer tests

[gopherbot]

Change https://go.dev/cl/456120 mentions this issue: runtime: remove arbitrary GOARCH constraints in finalizer tests