Re: [PATCH] sched: prefer an idle cpu vs an idle sibling for BALANCE_WAKE

[Josef Bacik <jbacik@fb.com>]

On 05/27/2015 05:03 PM, Rik van Riel wrote:
> On 05/27/2015 04:09 PM, Josef Bacik wrote:
>> On 05/26/2015 05:31 PM, Josef Bacik wrote:
>
>>> SD_BALANCE_WAKE is supposed to find us an idle cpu to run on, however
>>> it is just
>>> looking for an idle sibling, preferring affinity over all else.  This
>>> is not
>>> helpful in all cases, and SD_BALANCE_WAKE's job is to find us an idle
>>> cpu, not
>>> garuntee affinity.  Fix this by first trying to find an idle sibling,
>>> and then
>>> if the cpu is not idle fall through to the logic to find an idle cpu.
>>> With this
>>> patch we get slightly better performance than with our forward port of
>>> SD_WAKE_IDLE.  Thanks,
>>>
>>
>> I rigged up a test script to run the perf bench sched tests and give me
>> the numbers.  Here are the numbers
>>
>> 4.0
>>
>> Messaging: 56.934 Total runtime in seconds
>> Pipe: 105620.762 ops/sec
>>
>> 4.0 + my patch
>>
>> Messaging: 47.374
>> Pipe: 113691.199
>
> I did not get the email with your original patch,
> either to my inbox or my lkml folder, but I saw the
> patch on pastebin, and it looks good.
>
> When you resend it, please feel free to add my
>
> Acked-by: Rik van Riel <riel@redhat.com>
>
> Assuming the version you meant to email yesterday was
> the same one that you showed me on pastebin, of course :)
>

Ha yes it's the same, sorry I'm not sure what happened, I've resent it 
again from a different machine, let me know if you don't get the new one 
and I'll just send it from thunderbird.  Thanks,

Josef