lkml.org 
[lkml]   [2004]   [Jul]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: VM Problems in 2.6.7 (Too active OOM Killer)
    On Wed, Jul 14, 2004 at 04:47:04PM -0700, Peter Zaitsev wrote:
    > To be honest I do not really understand this OOM without swap problem at
    > all, why is it possible to move pages from ZONE_NORMAL to swap but not
    > to other zones ?

    the oom without swap you reproduced is not related to ZONE_NORMAL
    shortage. The pages in ZONE_NORMAL never goes into swap.

    the ZONE_NORMAL oom is a separate issue from the oom killing you
    reproduced. with 2.6.7 if you were hitting the ZONE_NORMAL shortage your
    machine would lockup and it would never oom-kill anything (Andrew just
    changed that in kernel CVS, so thanks to that change a ZONE_NORMAL
    shortage will not deadlock anymore in 2.6.8, but OTOH in 2.6.8 adding
    swap will not be enough anymore to workaround the oom-killing you
    reproduced).

    About the ZONE_NORMAL shortage without swap, rather than running
    cpu-cache-hungry memcopies from lowmemzone to highmem (or even worse to
    pass through swap like it happens in 2.6 mainline with swap enabled), I
    believe it's better to reserve some ram in the lowmem zone, 800M of ram
    on a 32G box should be a cheap price to pay compared to the cpu/IO cost
    involved in moving memory around during the bench.
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 14:04    [W:0.047 / U:181.540 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site