Re: 2.6.39-rc4+: Kernel leaking memory during FS scanning, regression?

From: Mike Frysinger
Date: Mon Apr 25 2011 - 03:47:53 EST


On Sun, Apr 24, 2011 at 22:42, KOSAKI Motohiro wrote:
>> On Sun, 24 April 2011 Bruno PrÃmont wrote:
>> > On an older system I've been running Gentoo's revdep-rebuild to check
>> > for system linking/*.la consistency and after doing most of the work the
>> > system starved more or less, just complaining about stuck tasks now and
>> > then.
>> > Memory usage graph as seen from userspace showed sudden quick increase of
>> > memory usage though only a very few MB were swapped out (c.f. attached RRD
>> > graph).
>>
>> Seems I've hit it once again (though detected before system was fully
>> stalled by trying to reclaim memory without success).
>>
>> This time it was during simple compiling...
>> Gathered info below:
>>
>> /proc/meminfo:
>> MemTotal: Â Â Â Â 480660 kB
>> MemFree: Â Â Â Â Â 64948 kB
>> Buffers: Â Â Â Â Â 10304 kB
>> Cached: Â Â Â Â Â Â 6924 kB
>> SwapCached: Â Â Â Â 4220 kB
>> Active: Â Â Â Â Â Â11100 kB
>> Inactive: Â Â Â Â Â15732 kB
>> Active(anon): Â Â Â 4732 kB
>> Inactive(anon): Â Â 4876 kB
>> Active(file): Â Â Â 6368 kB
>> Inactive(file): Â Â10856 kB
>> Unevictable: Â Â Â Â Â32 kB
>> Mlocked: Â Â Â Â Â Â Â32 kB
>> SwapTotal: Â Â Â Â524284 kB
>> SwapFree: Â Â Â Â 456432 kB
>> Dirty: Â Â Â Â Â Â Â Â80 kB
>> Writeback: Â Â Â Â Â Â 0 kB
>> AnonPages: Â Â Â Â Â6268 kB
>> Mapped: Â Â Â Â Â Â 2604 kB
>> Shmem: Â Â Â Â Â Â Â Â 4 kB
>> Slab: Â Â Â Â Â Â 250632 kB
>> SReclaimable: Â Â Â51144 kB
>> SUnreclaim: Â Â Â 199488 kB Â <--- look big as well...
>> KernelStack: Â Â Â131032 kB Â <--- what???
>
> KernelStack is used 8K bytes per thread. then, your system should have
> 16000 threads. but your ps only showed about 80 processes.
> Hmm... stack leak?

i might have a similar report for 2.6.39-rc4 (seems to be working fine
in 2.6.38.4), but for embedded Blackfin systems running gdbserver
processes over and over (so lots of short lived forks)

i wonder if you have a lot of zombies or otherwise unclaimed resources
? does `ps aux` show anything unusual ?
-mike
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/