Messages in this thread | | | Subject | Re: [PATCH]: Clean up of __alloc_pages | From | Rohit Seth <> | Date | Mon, 03 Oct 2005 09:55:58 -0700 |
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On Mon, 2005-10-03 at 08:34 -0700, Christoph Lameter wrote: > On Sat, 1 Oct 2005, Seth, Rohit wrote: > > > - goto zone_reclaim_retry; > > - } > > + if (order == 0) { > > + for (i = 0; (z = zones[i]) != NULL; i++) { > > + page = buffered_rmqueue(z, 0, gfp_mask, 0); > > + if (page) > > + goto got_pg; > > } > > - > > This is checking all zones for pages on the pcp before going the more > expensive route? >
That is right.
> Seems that this removes the logic intended to prefer local > allocations over remote pages present in the existing alloc_pages? There > is the danger that this modification will lead to the allocation of remote > pages even if local pages are available. Thus reducing performance. >
Good catch. I will up level the cpuset check in buffered_rmqueue rather then doing it in get_page_from_freelist. That should retain the current preferences for local pages.
> I would suggest to just check the first zone's pcp instead of all zones. >
Na. This for most cases will be ZONE_DMA pcp list having nothing much most of the time. And picking any other zone randomly will be exposed to faulty behavior.
Thanks, -rohit
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