code review 10321043: runtime: move stack segment cache from M to P

runtime: move stack segment cache from M to P
It seems that the cache does not go away completely in 1.3,
so I think it's worth it to move the cache from M to P as other caches.
Large Go programs (especially the ones that use swig/cgo) can have hundreds of threads,
currently max cache size is 256K, so it can save some dozens of MBs.

[dvyukov, 2014-02-25 13:54:49]

Hello golang-codereviews@googlegroups.com (cc: iant@golang.org, khr@golang.org,
rsc@golang.org),

I'd like you to review this change to
https://dvyukov%40google.com@code.google.com/p/go/

[gobot, 2014-02-27 16:51:17]

R=khr@golang.org (assigned by r@golang.org)

[dvyukov, 2014-02-27 17:08:20]

This can crash, because exitsyscall splits stack w/o P. It would be nice to
eventually make it not split stack "outside of world" (w/o P). But let' not
rush.
R=close

[bradfitz, 2014-02-27 17:13:32]

File a bug?



On Thu, Feb 27, 2014 at 9:08 AM, <dvyukov@google.com> wrote:

> This can crash, because exitsyscall splits stack w/o P. It would be nice
> to eventually make it not split stack "outside of world" (w/o P). But
> let' not rush.
> R=close
>
>
> https://codereview.appspot.com/10321043/
>
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[dvyukov, 2014-02-27 17:18:24]

https://code.google.com/p/go/issues/detail?id=7424

On Thu, Feb 27, 2014 at 9:13 PM, Brad Fitzpatrick <bradfitz@golang.org> wrote:
> File a bug?
>
>
>
> On Thu, Feb 27, 2014 at 9:08 AM, <dvyukov@google.com> wrote:
>>
>> This can crash, because exitsyscall splits stack w/o P. It would be nice
>> to eventually make it not split stack "outside of world" (w/o P). But
>> let' not rush.
>> R=close
>>
>>
>> https://codereview.appspot.com/10321043/
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "golang-codereviews" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to golang-codereviews+unsubscribe@googlegroups.com.
>> For more options, visit https://groups.google.com/groups/opt_out.
>
>