From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wj0-f198.google.com (mail-wj0-f198.google.com [209.85.210.198]) by kanga.kvack.org (Postfix) with ESMTP id BC6366B0038 for ; Mon, 28 Nov 2016 14:54:35 -0500 (EST) Received: by mail-wj0-f198.google.com with SMTP id xr1so22551986wjb.7 for ; Mon, 28 Nov 2016 11:54:35 -0800 (PST) Received: from gum.cmpxchg.org (gum.cmpxchg.org. [85.214.110.215]) by mx.google.com with ESMTPS id 185si27313712wmr.36.2016.11.28.11.54.34 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 28 Nov 2016 11:54:34 -0800 (PST) Date: Mon, 28 Nov 2016 14:54:21 -0500 From: Johannes Weiner Subject: Re: [PATCH] mm: page_alloc: High-order per-cpu page allocator v3 Message-ID: <20161128195421.GA22236@cmpxchg.org> References: <20161127131954.10026-1-mgorman@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161127131954.10026-1-mgorman@techsingularity.net> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , Christoph Lameter , Michal Hocko , Vlastimil Babka , Linux-MM , Linux-Kernel On Sun, Nov 27, 2016 at 01:19:54PM +0000, Mel Gorman wrote: > While it is recognised that this is a mixed bag of results, the patch > helps a lot more workloads than it hurts and intuitively, avoiding the > zone->lock in some cases is a good thing. > > Signed-off-by: Mel Gorman This seems like a net gain to me, and the patch loos good too. Acked-by: Johannes Weiner > @@ -255,6 +255,24 @@ enum zone_watermarks { > NR_WMARK > }; > > +/* > + * One per migratetype for order-0 pages and one per high-order up to > + * and including PAGE_ALLOC_COSTLY_ORDER. This may allow unmovable > + * allocations to contaminate reclaimable pageblocks if high-order > + * pages are heavily used. I think that should be fine. Higher order allocations rely on being able to compact movable blocks, not on reclaim freeing contiguous blocks, so poisoning reclaimable blocks is much less of a concern than poisoning movable blocks. And I'm not aware of any 0 < order < COSTLY movable allocations that would put movable blocks into an HO cache. -- 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