On Wed, Apr 24, 2019 at 03:46:24PM -0700, Andrew Morton wrote: > On Wed, 24 Apr 2019 10:04:03 +0100 Mel Gorman <[email protected]> > wrote: > > > On Tue, Apr 23, 2019 at 12:01:43PM -0700, Andrew Morton wrote: > > > On Tue, 23 Apr 2019 15:08:06 +0300 Andrey Ryabinin > > > <[email protected]> wrote: > > > > > > > Commit 0a79cdad5eb2 ("mm: use alloc_flags to record if kswapd can wake") > > > > removed setting of the ALLOC_NOFRAGMENT flag. Bring it back. > > > > > > What are the runtime effects of this fix? > > > > The runtime effect is that ALLOC_NOFRAGMENT behaviour is restored so > > that allocations are spread across local zones to avoid fragmentation > > due to mixing pageblocks as long as possible. > > OK, thanks. Is this worth a -stable backport?
Yes, but only for 5.0 obviously and both should be included if that is the case. I did not push for it initially as problems in this area are hard for a general user to detect and people have not complained about 5.0's fragmentation handling. -- Mel Gorman SUSE Labs
