(@orcaman 和/或 @OneOfOne 可能对这个感兴趣？)

我对这个想法很感兴趣，但我现在不能承诺。我脑海中浮现的一个想法需要破解运行时/哈希Map*,否则我们必须对键进行双重哈希。

非常有趣的任务，我很想接手这个。我认为它应该可以在Go1.10里程碑上实现。在我能100%承诺在适当的时候完成这个之前，我会再多考虑一下设计。

@orcaman What I wanted to do is something like https://github.com/OneOfOne/cmap/tree/master/v2 ,
I use a slightly modified version of this in my code, but I wanted to do that with sync.Map in a way, but that'd require a lot more runtime knowledge to be able to use runtime/map's hasher directly to do the sharding rather than double hash it.
Sadly I don't have the knowledge nor time to learn the internals of runtime/map right now.
By all means if you can do that, it'd be great or we can discuss it.

// very simple set/get benchmark using cmap, rwmutex map and sync.Map.

BenchmarkCMap/128-8     20000000               105 ns/op               0 B/op          0 allocs/op
BenchmarkCMap/256-8     20000000                88.6 ns/op             0 B/op          0 allocs/op
BenchmarkCMap/512-8     20000000                67.6 ns/op             0 B/op          0 allocs/op
BenchmarkCMap/1024-8    30000000                42.3 ns/op             0 B/op          0 allocs/op
BenchmarkCMap/2048-8    30000000                34.5 ns/op             0 B/op          0 allocs/op
BenchmarkCMap/4096-8    50000000                33.0 ns/op             0 B/op          0 allocs/op
BenchmarkMutexMap-8     10000000               196 ns/op               0 B/op          0 allocs/op
BenchmarkSyncMap-8      30000000                39.3 ns/op            16 B/op          1 allocs/op

我认为你可以使用锁片和脏Map，低位哈希值执行选择 - 但这需要访问内部哈希码。

@bcmills 我愿意尝试一下。有没有描述在实现是标准库一部分时使用内部设施的文档？

我不知道有没有好的入门文档，但也许@randall77或@aclements可以给你指明方向。

这真是个好主意。