Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

strings: use Builder in Repeat to avoid an allocation

Browse source 
name           old time/op    new time/op    delta
Repeat/5x1-4     95.9ns ± 2%    70.1ns ± 2%  -26.93%  (p=0.000 n=9+10)
Repeat/5x2-4      146ns ± 3%     100ns ± 2%  -31.99%  (p=0.000 n=10+10)
Repeat/5x6-4      203ns ± 3%     140ns ± 4%  -30.77%  (p=0.000 n=10+10)
Repeat/10x1-4     139ns ± 3%      92ns ± 4%  -34.08%  (p=0.000 n=10+10)
Repeat/10x2-4     188ns ± 4%     122ns ± 2%  -35.34%  (p=0.000 n=10+10)
Repeat/10x6-4     264ns ± 5%     179ns ± 4%  -32.15%  (p=0.000 n=10+10)

name           old alloc/op   new alloc/op   delta
Repeat/5x1-4      10.0B ± 0%      5.0B ± 0%  -50.00%  (p=0.000 n=10+10)
Repeat/5x2-4      32.0B ± 0%     16.0B ± 0%  -50.00%  (p=0.000 n=10+10)
Repeat/5x6-4      64.0B ± 0%     32.0B ± 0%  -50.00%  (p=0.000 n=10+10)
Repeat/10x1-4     32.0B ± 0%     16.0B ± 0%  -50.00%  (p=0.000 n=10+10)
Repeat/10x2-4     64.0B ± 0%     32.0B ± 0%  -50.00%  (p=0.000 n=10+10)
Repeat/10x6-4      128B ± 0%       64B ± 0%  -50.00%  (p=0.000 n=10+10)

Change-Id: I6619336da636df39c560f6cc481519f48c6e8176
GitHub-Last-Rev: 4b2c73f3bf
GitHub-Pull-Request: golang/go#25894
Reviewed-on: https://go-review.googlesource.com/118855
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This commit is contained in:
go101 2018-08-22 16:12:46 +00:00 • committed by Brad Fitzpatrick
parent 6a11e1e8db
commit 7a178df0bc
2 changed files with 26 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

11
src/strings/strings_test.go
View file

@ -1660,8 +1660,15 @@ func BenchmarkSplitNMultiByteSeparator(b *testing.B) {
}
func BenchmarkRepeat(b *testing.B) {
for i := 0; i < b.N; i++ {
Repeat("-", 80)
s := "0123456789"
for _, n := range []int{5, 10} {
for _, c := range []int{1, 2, 6} {
b.Run(fmt.Sprintf("%dx%d", n, c), func(b *testing.B) {
for i := 0; i < b.N; i++ {
Repeat(s[:n], c)
}
})
}
}
}