On Thu, 2016-02-25 at 09:30 +0900, Joonsoo Kim wrote: > On Wed, Feb 24, 2016 at 05:17:56PM -0500, Rik van Riel wrote: > > On Wed, 2016-02-24 at 14:15 -0800, David Rientjes wrote: > > > On Wed, 24 Feb 2016, Rik van Riel wrote: > > > > > > > For multi page allocations smaller than > > > > PAGE_ALLOC_COSTLY_ORDER, > > > > the kernel will do direct reclaim if compaction failed for any > > > > reason. This worked fine when Linux systems had 128MB RAM, but > > > > on my 24GB system I frequently see higher order allocations > > > > free up over 3GB of memory, pushing all kinds of things into > > > > swap, and slowing down applications. > > > > > > > > > > Just curious, are these higher order allocations typically done > > > by > > > the > > > slub allocator or where are they coming from? > > > > These are slab allocator ones, indeed. > > > > The allocations seem to be order 2 and 3, mostly > > on behalf of the inode cache and alloc_skb. > > Hello, Rik. > > Could you tell me the kernel version you tested? > > Commit 45eb00cd3a03 (mm/slub: don't wait for high-order page > allocation) changes slub allocator's behaviour that high order > allocation request by slub doesn't cause direct reclaim.
The system I observed the problem on has a 4.2 based kernel on it. That would explain. Are we sure the problem is limited just to slub, though? -- All Rights Reversed.
signature.asc
Description: This is a digitally signed message part
