From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH]: Clean up of __alloc_pages From: Rohit Seth In-Reply-To: References: <20051001120023.A10250@unix-os.sc.intel.com> Content-Type: text/plain Date: Mon, 03 Oct 2005 09:55:58 -0700 Message-Id: <1128358558.8472.13.camel@akash.sc.intel.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: akpm@osdl.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org