runtime: use a high res timer to signal io completion ports on windows
GetQueuedCompletionStatusEx has a ~16ms timeout resolution. Use a
WaitCompletionPacket associated with the I/O Completion Port (IOCP)
and a high resolution timer so the IOCP is signaled on timer expiry,
therefore improving the GetQueuedCompletionStatusEx timeout resolution.
BenchmarkSleep from the time package shows an important improvement:
goos: windows
goarch: amd64
pkg: time
cpu: Intel(R) Core(TM) i7-10850H CPU @ 2.70GHz
│ old.txt │ new.txt │
│ sec/op │ sec/op vs base │
Sleep-12 1258.5µ ± 5% 250.7µ ± 1% -80.08% (p=0.000 n=20)
Fixes #44343.
Change-Id: I79fc09e34dddfc49e0e23c3d1d0603926c22a11d
Reviewed-on: https://go-review.googlesource.com/c/go/+/488675 Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Quim Muntal <quimmuntal@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Bryan Mills <bcmills@google.com> Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>