On Wed, Aug 26, 2015 at 04:53:52PM +0200, Michal Hocko wrote: > > > > Overall, this is a small reduction but the reserves are small relative to the > > number of allocation requests. In early versions of the patch, the failure > > rate reduced by a much larger amount but that required much larger reserves > > and perversely made atomic allocations seem more reliable than regular allocations. > > Have you considered a counter for vmstat/zoneinfo so that we have an overview > about the memory consumed for this reserve? > It should already be available in /proc/pagetypeinfo > > Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> > > Acked-by: Michal Hocko <mhocko@xxxxxxxx> > > [...] > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index d5ce050ebe4f..2415f882b89c 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > [...] > > @@ -1645,10 +1725,16 @@ __rmqueue_fallback(struct zone *zone, unsigned int order, int start_migratetype) > > * Call me with the zone->lock already held. > > */ > > static struct page *__rmqueue(struct zone *zone, unsigned int order, > > - int migratetype) > > + int migratetype, gfp_t gfp_flags) > > { > > struct page *page; > > > > + if (unlikely(order && (gfp_flags & __GFP_ATOMIC))) { > > + page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC); > > + if (page) > > + goto out; > > I guess you want to change migratetype to MIGRATE_HIGHATOMIC in the > successful case so the tracepoint reports this properly. > Yes, thanks. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>