[lkml]   [2018]   [Jul]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v3 3/7] mm, slab: allocate off-slab freelists as reclaimable when appropriate
On Wed, Jul 18, 2018 at 03:36:16PM +0200, Vlastimil Babka wrote:
> In SLAB, OFF_SLAB caches allocate management structures (currently just the
> freelist) from kmalloc caches when placement in a slab page together with
> objects would lead to suboptimal memory usage. For SLAB_RECLAIM_ACCOUNT caches,
> we can allocate the freelists from the newly introduced reclaimable kmalloc
> caches, because shrinking the OFF_SLAB cache will in general result to freeing
> of the freelists as well. This should improve accounting and anti-fragmentation
> a bit.
> Signed-off-by: Vlastimil Babka <>

I'm not quite convinced by this one. The freelist cache is tied to the
lifetime of the slab and not the objects. A single freelist can be reclaimed
eventually but for caches with many objects per slab, it could take a lot
of shrinking random objects to reclaim one freelist. Functionally the
patch appears to be fine.

Mel Gorman

 \ /
  Last update: 2018-07-19 10:36    [W:0.136 / U:3.284 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site