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* unfair scheduling with tbb application observed, could it be a kernel issue?
@ 2012-08-06 14:04 Pedro Larroy
  2012-08-06 14:25 ` Mike Galbraith
  0 siblings, 1 reply; 6+ messages in thread
From: Pedro Larroy @ 2012-08-06 14:04 UTC (permalink / raw)
  To: linux-kernel

Hi

I think we are observing unfair scheduling of processes that use intel
TBB thread scheduler, as we have several processes with nice of 19 and
ioniced idle, and somehow the process with nice 0 should be getting
more than 1000% cpu

Any ideas? Kernel is 3.0.0.-17-generic on unbutu 11.10.


Avg[||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||99.6%]
Tasks: 331; 81 running
Mem[||||||||||||||||||||||||||||||||||||||||||||||||||||||||36386/96868MB]
Load average: 76.99 46.08 34.32
Swp[|||||||||
534/4099MB] Time: 15:51:51
  PID USER     PRI  NI  VIRT   RES   SHR S CPU% MEM%   TIME+  Command
10597 disco     39  19 6772M 6366M 14384 R 636.  6.6 37:56.63
/map_store/developers/disco/12_08_06-13_53_1344254009-j3UGmL/mmcc -X
178 -c /map_store/de
11629 visciano  20   0 6106M 5504M 18668 R 585.  5.7 39:02.15
build/release/mmcc -D --compact -f 8 -h bfmapcomp03.europe.nokia.com
-d 1521 -s LDMTEST -
10235 disco     39  19 4566M 4190M 12512 R 197.  4.3 25:13.58
/map_store/developers/disco/12_08_06-13_53_1344254009-j3UGmL/mmcc -X
183 -c /map_store/de
11599 disco     39  19 4935M 4644M 12572 R 188.  4.8 15:44.48
/map_store/developers/disco/12_08_06-13_53_1344254009-j3UGmL/mmcc -X
176 -c /map_store/de
11996 disco     39  19 4407M 4164M 12580 R 103.  4.3 12:08.25
/map_store/developers/disco/12_08_06-13_53_1344254009-j3UGmL/mmcc -X
174 -c /map_store/de
12630 disco     39  19 1804M 1589M 12248 R 101.  1.6  4:31.51
/map_store/developers/disco/12_08_06-13_53_1344254009-j3UGmL/mmcc -X
172 -c /map_store/de

Another example, the processes at 100% not being throttled at all when
having more processes waiting with higher priority:


Tasks: 559 total,  37 running, 522 sleeping,   0 stopped,   0 zombie
Cpu(s): 67.8%us, 16.0%sy, 13.0%ni,  1.7%id,  0.6%wa,  0.0%hi,  1.0%si,  0.0%st
Mem:  98998032k total, 97444688k used,  1553344k free,    53772k buffers
Swap:  4198316k total,   704860k used,  3493456k free, 73270776k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
14373 disco     39  19 8734m 6.9g  12m R  107  7.3  36:09.72 mmcc
15293 disco     39  19 3174m 1.4g  12m R  101  1.5  19:33.79 mmcc
20341 disco     39  19 2735m 1.1g  12m R  101  1.1   8:40.38 mmcc
18241 disco     39  19 3040m 1.3g  11m R  100  1.4  14:27.91 mmcc
15204 disco     39  19 5418m 3.7g  12m R   99  3.9  20:53.89 mmcc
24901 larroy    20   0  327m 296m 4276 R   88  0.3   0:04.14 cc1plus
24942 larroy    20   0  193m 159m 4008 R   87  0.2   0:01.47 cc1plus
24862 larroy    20   0  417m 388m 7992 R   84  0.4   0:07.02 cc1plus
24959 larroy    20   0  184m 153m 4008 R   80  0.2   0:01.32 cc1plus
24935 larroy    20   0  254m 222m 4024 R   77  0.2   0:02.44 cc1plus
24919 larroy    20   0  336m 301m 4036 R   76  0.3   0:03.61 cc1plus
24972 larroy    20   0 43160  15m 2332 R   76  0.0   0:00.95 cc1plus
24918 larroy    20   0  287m 255m 4024 R   70  0.3   0:02.99 cc1plus
24962 larroy    20   0 44872  17m 2332 R   69  0.0   0:01.23 cc1plus
24976 larroy    20   0 41212  14m 2332 R   66  0.0   0:00.67 cc1plus
24501 larroy    20   0  687m 657m 8044 R   64  0.7   0:22.97 cc1plus
24933 larroy    20   0  211m 177m 4008 R   62  0.2   0:01.79 cc1plus
24899 larroy    20   0  327m 296m 4276 R   57  0.3   0:04.25 cc1plus

This is 3.2.0-26-generic on ubuntu 12.04

Regards.

Pedro.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: unfair scheduling with tbb application observed, could it be a kernel issue?
  2012-08-06 14:04 unfair scheduling with tbb application observed, could it be a kernel issue? Pedro Larroy
@ 2012-08-06 14:25 ` Mike Galbraith
  2012-08-06 14:28   ` Pedro Larroy
  0 siblings, 1 reply; 6+ messages in thread
From: Mike Galbraith @ 2012-08-06 14:25 UTC (permalink / raw)
  To: Pedro Larroy; +Cc: linux-kernel

On Mon, 2012-08-06 at 16:04 +0200, Pedro Larroy wrote: 
> Hi
> 
> I think we are observing unfair scheduling of processes that use intel
> TBB thread scheduler, as we have several processes with nice of 19 and
> ioniced idle, and somehow the process with nice 0 should be getting
> more than 1000% cpu
.. 
> Tasks: 559 total,  37 running, 522 sleeping,   0 stopped,   0 zombie
> Cpu(s): 67.8%us, 16.0%sy, 13.0%ni,  1.7%id,  0.6%wa,  0.0%hi,  1.0%si,  0.0%st
> Mem:  98998032k total, 97444688k used,  1553344k free,    53772k buffers
> Swap:  4198316k total,   704860k used,  3493456k free, 73270776k cached
> 
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
> 14373 disco     39  19 8734m 6.9g  12m R  107  7.3  36:09.72 mmcc
> 15293 disco     39  19 3174m 1.4g  12m R  101  1.5  19:33.79 mmcc
> 20341 disco     39  19 2735m 1.1g  12m R  101  1.1   8:40.38 mmcc
> 18241 disco     39  19 3040m 1.3g  11m R  100  1.4  14:27.91 mmcc
> 15204 disco     39  19 5418m 3.7g  12m R   99  3.9  20:53.89 mmcc
> 24901 larroy    20   0  327m 296m 4276 R   88  0.3   0:04.14 cc1plus
> 24942 larroy    20   0  193m 159m 4008 R   87  0.2   0:01.47 cc1plus
> 24862 larroy    20   0  417m 388m 7992 R   84  0.4   0:07.02 cc1plus
> 24959 larroy    20   0  184m 153m 4008 R   80  0.2   0:01.32 cc1plus
> 24935 larroy    20   0  254m 222m 4024 R   77  0.2   0:02.44 cc1plus
> 24919 larroy    20   0  336m 301m 4036 R   76  0.3   0:03.61 cc1plus
> 24972 larroy    20   0 43160  15m 2332 R   76  0.0   0:00.95 cc1plus
> 24918 larroy    20   0  287m 255m 4024 R   70  0.3   0:02.99 cc1plus
> 24962 larroy    20   0 44872  17m 2332 R   69  0.0   0:01.23 cc1plus
> 24976 larroy    20   0 41212  14m 2332 R   66  0.0   0:00.67 cc1plus
> 24501 larroy    20   0  687m 657m 8044 R   64  0.7   0:22.97 cc1plus
> 24933 larroy    20   0  211m 177m 4008 R   62  0.2   0:01.79 cc1plus
> 24899 larroy    20   0  327m 296m 4276 R   57  0.3   0:04.25 cc1plus

Are tasks running in per user cgroups or such?  If so, you'd need to
adjust group shares.

-Mike


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: unfair scheduling with tbb application observed, could it be a kernel issue?
  2012-08-06 14:25 ` Mike Galbraith
@ 2012-08-06 14:28   ` Pedro Larroy
  2012-08-06 14:38     ` Mike Galbraith
  0 siblings, 1 reply; 6+ messages in thread
From: Pedro Larroy @ 2012-08-06 14:28 UTC (permalink / raw)
  To: Mike Galbraith; +Cc: linux-kernel

I didn't enable cgroups explicitly, and don't have userspace tools for
that installed.

Thanks.

Pedro.

On Mon, Aug 6, 2012 at 4:25 PM, Mike Galbraith <efault@gmx.de> wrote:
> On Mon, 2012-08-06 at 16:04 +0200, Pedro Larroy wrote:
>> Hi
>>
>> I think we are observing unfair scheduling of processes that use intel
>> TBB thread scheduler, as we have several processes with nice of 19 and
>> ioniced idle, and somehow the process with nice 0 should be getting
>> more than 1000% cpu
> ..
>> Tasks: 559 total,  37 running, 522 sleeping,   0 stopped,   0 zombie
>> Cpu(s): 67.8%us, 16.0%sy, 13.0%ni,  1.7%id,  0.6%wa,  0.0%hi,  1.0%si,  0.0%st
>> Mem:  98998032k total, 97444688k used,  1553344k free,    53772k buffers
>> Swap:  4198316k total,   704860k used,  3493456k free, 73270776k cached
>>
>>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>> 14373 disco     39  19 8734m 6.9g  12m R  107  7.3  36:09.72 mmcc
>> 15293 disco     39  19 3174m 1.4g  12m R  101  1.5  19:33.79 mmcc
>> 20341 disco     39  19 2735m 1.1g  12m R  101  1.1   8:40.38 mmcc
>> 18241 disco     39  19 3040m 1.3g  11m R  100  1.4  14:27.91 mmcc
>> 15204 disco     39  19 5418m 3.7g  12m R   99  3.9  20:53.89 mmcc
>> 24901 larroy    20   0  327m 296m 4276 R   88  0.3   0:04.14 cc1plus
>> 24942 larroy    20   0  193m 159m 4008 R   87  0.2   0:01.47 cc1plus
>> 24862 larroy    20   0  417m 388m 7992 R   84  0.4   0:07.02 cc1plus
>> 24959 larroy    20   0  184m 153m 4008 R   80  0.2   0:01.32 cc1plus
>> 24935 larroy    20   0  254m 222m 4024 R   77  0.2   0:02.44 cc1plus
>> 24919 larroy    20   0  336m 301m 4036 R   76  0.3   0:03.61 cc1plus
>> 24972 larroy    20   0 43160  15m 2332 R   76  0.0   0:00.95 cc1plus
>> 24918 larroy    20   0  287m 255m 4024 R   70  0.3   0:02.99 cc1plus
>> 24962 larroy    20   0 44872  17m 2332 R   69  0.0   0:01.23 cc1plus
>> 24976 larroy    20   0 41212  14m 2332 R   66  0.0   0:00.67 cc1plus
>> 24501 larroy    20   0  687m 657m 8044 R   64  0.7   0:22.97 cc1plus
>> 24933 larroy    20   0  211m 177m 4008 R   62  0.2   0:01.79 cc1plus
>> 24899 larroy    20   0  327m 296m 4276 R   57  0.3   0:04.25 cc1plus
>
> Are tasks running in per user cgroups or such?  If so, you'd need to
> adjust group shares.
>
> -Mike
>

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: unfair scheduling with tbb application observed, could it be a kernel issue?
  2012-08-06 14:28   ` Pedro Larroy
@ 2012-08-06 14:38     ` Mike Galbraith
  2012-08-06 14:46       ` Mike Galbraith
  0 siblings, 1 reply; 6+ messages in thread
From: Mike Galbraith @ 2012-08-06 14:38 UTC (permalink / raw)
  To: Pedro Larroy; +Cc: linux-kernel

On Mon, 2012-08-06 at 16:28 +0200, Pedro Larroy wrote: 
> I didn't enable cgroups explicitly, and don't have userspace tools for
> that installed.

You don't userspace tools.  cat /proc/<pid>/cgroup will show the group.

-Mike


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: unfair scheduling with tbb application observed, could it be a kernel issue?
  2012-08-06 14:38     ` Mike Galbraith
@ 2012-08-06 14:46       ` Mike Galbraith
  2012-08-06 15:14         ` Mike Galbraith
  0 siblings, 1 reply; 6+ messages in thread
From: Mike Galbraith @ 2012-08-06 14:46 UTC (permalink / raw)
  To: Pedro Larroy; +Cc: linux-kernel

On Mon, 2012-08-06 at 16:38 +0200, Mike Galbraith wrote: 
> On Mon, 2012-08-06 at 16:28 +0200, Pedro Larroy wrote: 
> > I didn't enable cgroups explicitly, and don't have userspace tools for
> > that installed.
> 
> You don't userspace tools.  cat /proc/<pid>/cgroup will show the group.
           ^need

Did you mean "didn't explicitly enable" as in..

marge:~ # zcat /proc/config.gz|grep CONFIG_CGROUP_SCHED
# CONFIG_CGROUP_SCHED is not set

-Mike


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: unfair scheduling with tbb application observed, could it be a kernel issue?
  2012-08-06 14:46       ` Mike Galbraith
@ 2012-08-06 15:14         ` Mike Galbraith
  0 siblings, 0 replies; 6+ messages in thread
From: Mike Galbraith @ 2012-08-06 15:14 UTC (permalink / raw)
  To: Pedro Larroy; +Cc: linux-kernel

Ok, with the sched_debug info you sent offline, booting with noautogroup
appended to the kernel command line should fix it up for you.  You've
got autogroup enabled, which creates automagic per session task groups.

-Mike  


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2012-08-06 15:14 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-08-06 14:04 unfair scheduling with tbb application observed, could it be a kernel issue? Pedro Larroy
2012-08-06 14:25 ` Mike Galbraith
2012-08-06 14:28   ` Pedro Larroy
2012-08-06 14:38     ` Mike Galbraith
2012-08-06 14:46       ` Mike Galbraith
2012-08-06 15:14         ` Mike Galbraith

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