Re: kswapd0: wxcessive CPU usage

Andrew Morton
2012-10-11T22:14:15Z

On Thu, 11 Oct 2012 10:52:28 +0200
Jiri Slaby <jslaby@suse.cz> wrote:

> with 3.6.0-next-20121008, kswapd0 is spinning my CPU at 100% for 1
> minute or so. If I try to suspend to RAM, this trace appears:
> kswapd0 R running task 0 577 2 0x00000000
> 0000000000000000 00000000000000c0 cccccccccccccccd ffff8801c4146800
> ffff8801c4b15c88 ffffffff8116ee05 0000000000003e32 ffff8801c3a79000
> ffff8801c4b15ca8 ffffffff8116fdf8 ffff8801c480f398 ffff8801c3a79000
> Call Trace:
> [<ffffffff8116ee05>] ? put_super+0x25/0x40
> [<ffffffff8116fdd4>] ? grab_super_passive+0x24/0xa0
> [<ffffffff8116ff99>] ? prune_super+0x149/0x1b0
> [<ffffffff81131531>] ? shrink_slab+0xa1/0x2d0
> [<ffffffff8113452d>] ? kswapd+0x66d/0xb60
> [<ffffffff81133ec0>] ? try_to_free_pages+0x180/0x180
> [<ffffffff810a2770>] ? kthread+0xc0/0xd0
> [<ffffffff810a26b0>] ? kthread_create_on_node+0x130/0x130
> [<ffffffff816a6c9c>] ? ret_from_fork+0x7c/0x90
> [<ffffffff810a26b0>] ? kthread_create_on_node+0x130/0x130

Could you please do a sysrq-T a few times while it's spinning, to
confirm that this trace is consistently the culprit?