lkml.org 
[lkml]   [2016]   [Apr]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 14/14] mm, oom, compaction: prevent from should_compact_retry looping for ever for costly orders
    On Thu 28-04-16 10:59:22, Vlastimil Babka wrote:
    > On 04/20/2016 09:47 PM, Michal Hocko wrote:
    > >From: Michal Hocko <mhocko@suse.com>
    > >
    > >"mm: consider compaction feedback also for costly allocation" has
    > >removed the upper bound for the reclaim/compaction retries based on the
    > >number of reclaimed pages for costly orders. While this is desirable
    > >the patch did miss a mis interaction between reclaim, compaction and the
    > >retry logic.
    >
    > Hmm perhaps reversing the order of patches 13 and 14 would be a bit safer
    > wrt future bisections then? Add compaction_zonelist_suitable() first with
    > the reasoning, and then immediately use it in the other patch.

    Hmm, I do not think the risk is high. This would require the allocate
    GFP_REPEAT large orders to the last drop which is not usual. I found the
    ordering more logical to argue about because this patch will be mostly
    noop for costly orders without 13 and !costly allocations retry
    endlessly anyway. So I would prefer this ordering even though there is
    a window where an extreme load can lockup. I do not expect people
    shooting their head during bisection.

    [...]
    > >
    > >[vbabka@suse.cz: fix classzone_idx vs. high_zoneidx usage in
    > >compaction_zonelist_suitable]
    > >Signed-off-by: Michal Hocko <mhocko@suse.com>
    >
    > Acked-by: Vlastimil Babka <vbabka@suse.cz>

    Thanks!

    --
    Michal Hocko
    SUSE Labs

    \
     
     \ /
      Last update: 2016-04-28 15:01    [W:2.401 / U:0.800 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site