LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Dave Chinner <david@fromorbit.com>
To: Claudio Martins <ctpm@ist.utl.pt>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Order 0 page allocation failure under heavy I/O load
Date: Mon, 27 Oct 2008 17:22:16 +1100	[thread overview]
Message-ID: <20081027062216.GH11948@disturbed> (raw)
In-Reply-To: <200810270547.31123.ctpm@ist.utl.pt>

On Mon, Oct 27, 2008 at 06:47:31AM +0100, Claudio Martins wrote:
> On Sunday 26 October 2008, Dave Chinner wrote:
> 
> > The host will hang for tens of seconds at a time with both CPU cores
> > pegged at 100%, and eventually I get this in dmesg:
> >
> > [1304740.261506] linux: page allocation failure. order:0, mode:0x10000
> > [1304740.261516] Pid: 10705, comm: linux Tainted: P          2.6.26-1-amd64
> 
>  Hello,
> 
>  Have you tried to increase vm.min_free_kbytes to something higher, that is 
> >=30000?

No, because I've found the XFS bug the workload was triggering so
I don't need to run it anymore.

I reported the problem because it appears that we've reported an
allocation failure without very much reclaim scanning (64 pages in
DMA zone, 0 pages in DMA32 zone), and there is apparently pages
available for allocation in the DMA zone:

1304740.262136] Node 0 DMA: 160*4kB 82*8kB 32*16kB 11*32kB 8*64kB 4*128kB 3*256kB 0*512kB 0*1024kB 0*2048kB 1*4096kB = 8048kB

So it appears that memory reclaim has not found the free pages it
apparently has available....

Fundamentally, I/O from a single CPU to a single disk on a machine
with 2GB RAM should not be able to cause allocation failures at all,
especially when the I/O is pure data I/O to a single file. Something
in the default config is busted if I can do that, and that's why
I reported the bug.

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

  reply	other threads:[~2008-10-27  6:22 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-26 22:57 Dave Chinner
2008-10-27  5:47 ` Claudio Martins
2008-10-27  6:22   ` Dave Chinner [this message]
2008-10-27  8:04     ` Peter Zijlstra
2008-10-27 10:17       ` Dave Chinner
2008-10-28 13:20 ` Miquel van Smoorenburg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20081027062216.GH11948@disturbed \
    --to=david@fromorbit.com \
    --cc=ctpm@ist.utl.pt \
    --cc=linux-kernel@vger.kernel.org \
    --subject='Re: Order 0 page allocation failure under heavy I/O load' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).