code review 8174043: bytes: Benchmark Buffer's compactions

bytes: Benchmark Buffer's compactions

This benchmark verifies that CL #8173043 reduces time spent
sliding the Buffer's contents.

Results without and with CL #8173043 applied:
benchmark                        old ns/op    new ns/op    delta
BenchmarkBufferFullSmallReads       755336       175054  -76.82%

[robryk, 2013-03-29 20:50:15]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://code.google.com/p/go/

[bradfitz, 2013-03-29 20:52:11]

Could you add a little comment above the benchmark with a summary and
referencing the Issue number?  (which has all the links back to the patches)

On Fri, Mar 29, 2013 at 1:50 PM, <robryk@gmail.com> wrote:

> Reviewers: golang-dev1,
>
> Message:
> Hello golang-dev@googlegroups.com,
>
> I'd like you to review this change to
> https://code.google.com/p/go/
>
>
> Description:
> bytes: Benchmark Buffer's compactions
>
> This benchmark verifies that CL #8173043 reduces time spent
> sliding the Buffer's contents.
>
> Results without and with CL #8173043 applied:
> benchmark                        old ns/op    new ns/op    delta
> BenchmarkBufferFullSmallReads       755336       175054  -76.82%
>
> Please review this at
https://codereview.appspot.**com/8174043/<https://codereview.appspot.com/8174...
>
> Affected files:
>   M src/pkg/bytes/buffer_test.go
>
>
> Index: src/pkg/bytes/buffer_test.go
> ==============================**==============================**=======
> --- a/src/pkg/bytes/buffer_test.go
> +++ b/src/pkg/bytes/buffer_test.go
> @@ -507,3 +507,18 @@
>                 }
>         }
>  }
> +
> +func BenchmarkBufferFullSmallReads(**b *testing.B) {
> +       buf := make([]byte, 1024)
> +       for i := 0; i < b.N; i++ {
> +               var b Buffer
> +               b.Write(buf)
> +               for b.Len()+20 < b.Cap() {
> +                       b.Write(buf[:10])
> +               }
> +               for i := 0; i < 5<<10; i++ {
> +                       b.Read(buf[:1])
> +                       b.Write(buf[:1])
> +               }
> +       }
> +}
>
>
> --
>
> ---You received this message because you are subscribed to the Google
> Groups "golang-dev" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to
golang-dev+unsubscribe@**googlegroups.com<golang-dev%2Bunsubscribe@googlegrou...
> .
> For more options, visit
https://groups.google.com/**groups/opt_out<https://groups.google.com/groups/o...
> .
>
>
>

[robryk, 2013-03-29 20:57:41]

Added a reference to the issue.

[bradfitz, 2013-03-29 21:05:17]

LGTM

On Fri, Mar 29, 2013 at 1:57 PM, <robryk@gmail.com> wrote:

> Added a reference to the issue.
>
>
https://codereview.appspot.**com/8174043/<https://codereview.appspot.com/8174...
>

[bradfitz, 2013-03-29 21:06:46]

abort: cannot find robryk@gmail.com in CONTRIBUTORS

You need to fill out a CLA.

See http://golang.org/doc/contribute.html#copyright

Let us know when done.


On Fri, Mar 29, 2013 at 2:05 PM, Brad Fitzpatrick <bradfitz@golang.org>wrote:

> LGTM
>
>
> On Fri, Mar 29, 2013 at 1:57 PM, <robryk@gmail.com> wrote:
>
>> Added a reference to the issue.
>>
>>
https://codereview.appspot.**com/8174043/<https://codereview.appspot.com/8174...
>>
>
>

[robryk, 2013-03-29 21:15:30]

On Fri, Mar 29, 2013 at 10:06 PM, Brad Fitzpatrick <bradfitz@golang.org> wrote:
> abort: cannot find robryk@gmail.com in CONTRIBUTORS
>
> You need to fill out a CLA.
>
> See http://golang.org/doc/contribute.html#copyright
>
> Let us know when done.
Done (I've submitted the Google Docs form).

[bradfitz, 2013-03-29 21:17:11]

*** Submitted as https://code.google.com/p/go/source/detail?r=192e257c6507 ***

bytes: Benchmark Buffer's compactions

This benchmark verifies that CL #8173043 reduces time spent
sliding the Buffer's contents.

Results without and with CL #8173043 applied:
benchmark                        old ns/op    new ns/op    delta
BenchmarkBufferFullSmallReads       755336       175054  -76.82%

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/8174043

Committer: Brad Fitzpatrick <bradfitz@golang.org>