Permalink
Browse files

sync: improve Pool performance

Rewrite indexLocal to achieve higher performance.

Performance results on linux/amd64:

name            old time/op  new time/op  delta
Pool-4          19.1ns ± 2%  10.1ns ± 1%  -47.15%  (p=0.000 n=10+8)
PoolOverflow-4  3.11µs ± 1%  2.10µs ± 2%  -32.66%  (p=0.000 n=10+10)

Performance results on linux/386:

name            old time/op  new time/op  delta
Pool-4          20.0ns ± 2%  13.1ns ± 1%  -34.59%  (p=0.000 n=10+9)
PoolOverflow-4  3.51µs ± 1%  2.49µs ± 0%  -28.99%  (p=0.000 n=10+8)

Change-Id: I7d57a2d4cd47ec43d09ca1267bde2e3f05a9faa9
Reviewed-on: https://go-review.googlesource.com/40913
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
  • Loading branch information...
valyala authored and ianlancetaylor committed Apr 17, 2017
1 parent c239fbb commit af5c95117b26e22d942a12e15bdc8e25607f738c
Showing with 2 additions and 1 deletion.
  1. +2 −1 src/sync/pool.go
View
@@ -241,7 +241,8 @@ func init() {
}
func indexLocal(l unsafe.Pointer, i int) *poolLocal {
- return &(*[1000000]poolLocal)(l)[i]
+ lp := unsafe.Pointer(uintptr(l) + uintptr(i)*unsafe.Sizeof(poolLocal{}))
+ return (*poolLocal)(lp)
}
// Implemented in runtime.

0 comments on commit af5c951

Please sign in to comment.