sync: support for sharded values #64845

qiulaidongfeng · 2023-12-22T14:22:45Z

This CL deliberately makes the zero value of Sharded unusable.
Purpose to force that NewSharded initialization must be used.
And because Sharded methods only have read operations.
So Sharded can operate without locks or atoms,
and multiple goroutines can use a Sharded at the same time.

goos: windows
goarch: amd64
pkg: sync
cpu: AMD Ryzen 7 7840HS w/ Radeon 780M Graphics
BenchmarkSharedAtomicInt64/1-16 726 1608184 ns/op
BenchmarkSharedAtomicInt64/2-16 1828 646521 ns/op
BenchmarkSharedAtomicInt64/4-16 3958 316261 ns/op
BenchmarkSharedAtomicInt64/8-16 6428 172238 ns/op
BenchmarkSharedAtomicInt64/16-16 16488 73966 ns/op

Fixes #18802

This CL deliberately makes the zero value of Sharded unusable. Purpose to force that NewSharded initialization must be used. And because Sharded methods only have read operations. So Sharded can operate without locks or atoms, and multiple goroutines can use a Sharded at the same time. Fixes golang#18802

gopherbot · 2023-12-22T14:31:13Z

This PR (HEAD: d748970) has been imported to Gerrit for code review.

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gopherbot · 2023-12-23T02:41:13Z

This PR (HEAD: d18fe9a) has been imported to Gerrit for code review.

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gopherbot · 2023-12-23T02:47:10Z

Message from qiulaidongfeng:

Patch Set 2: Run-TryBot+1