code review 8479043: test: fix flaky NaN-key map complexity test

test: fix flaky NaN-key map complexity test

Don't measure wall time in map.go. Keep it portable
and only test NaN, but not time.

Move time tests to mapnan.go and only measure user CPU time,
not wall time. It builds on Darwin and Linux, the primary
platforms where people hack on the runtime & in particular
maps. The runtime is shared, though, so we don't need it to
run on all of the platforms.

Fixes flaky build failures like:
http://build.golang.org/log/ba67eceefdeaa1142cb6c990a62fa3ffd8fd73f8

[bradfitz, 2013-04-07 18:32:37]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[r, 2013-04-07 18:47:21]

LGTM

https://codereview.appspot.com/8479043/diff/5001/test/mapnan.go
File test/mapnan.go (right):

https://codereview.appspot.com/8479043/diff/5001/test/mapnan.go#newcode47
test/mapnan.go:47: n := 30000 // 0.02 seconds on a MacBook Air
might as well be more specific. macbook airs may be around forever. something
like Late 2010 MacBook Air or 1.4GHz Core Duo MacBook Air

https://codereview.appspot.com/8479043/diff/5001/test/mapnan.go#newcode59
test/mapnan.go:59: return
d

[bradfitz, 2013-04-07 18:53:06]

https://codereview.appspot.com/8479043/diff/5001/test/mapnan.go
File test/mapnan.go (right):

https://codereview.appspot.com/8479043/diff/5001/test/mapnan.go#newcode47
test/mapnan.go:47: n := 30000 // 0.02 seconds on a MacBook Air
On 2013/04/07 18:47:21, r wrote:
> might as well be more specific. macbook airs may be around forever. something
> like Late 2010 MacBook Air or 1.4GHz Core Duo MacBook Air

This is just code movement. I don't know whose MacBook Air this was, nor its
specs.  I assume Russ', which IIRC is the same as mine.  I'll update it to say
Mid 2011, which is what my system info says here.

https://codereview.appspot.com/8479043/diff/5001/test/mapnan.go#newcode59
test/mapnan.go:59: return
On 2013/04/07 18:47:21, r wrote:
> d

will do. also just code movement, though.

[bradfitz, 2013-04-07 18:56:18]

*** Submitted as https://code.google.com/p/go/source/detail?r=845066f7e0df ***

test: fix flaky NaN-key map complexity test

Don't measure wall time in map.go. Keep it portable
and only test NaN, but not time.

Move time tests to mapnan.go and only measure user CPU time,
not wall time. It builds on Darwin and Linux, the primary
platforms where people hack on the runtime & in particular
maps. The runtime is shared, though, so we don't need it to
run on all of the platforms.

Fixes flaky build failures like:
http://build.golang.org/log/ba67eceefdeaa1142cb6c990a62fa3ffd8fd73f8

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/8479043

[remyoudompheng, 2013-04-08 07:01:12]

$ go run run.go -show_skips
??                   linkx.go            : skipped; unknown pattern: $G
skip                 mapnan.go           : +build darwin,linux
[...]

The build tag is always false.

[bradfitz, 2013-04-08 07:03:10]

That fixes the flakiness!



On Mon, Apr 8, 2013 at 12:01 AM, <remyoudompheng@gmail.com> wrote:

> $ go run run.go -show_skips
> ??                   linkx.go            : skipped; unknown pattern: $G
> skip                 mapnan.go           : +build darwin,linux
> [...]
>
> The build tag is always false.
>
>
https://codereview.appspot.**com/8479043/<https://codereview.appspot.com/8479...
>