From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f200.google.com (mail-io0-f200.google.com [209.85.223.200]) by kanga.kvack.org (Postfix) with ESMTP id 47CE66B0038 for ; Wed, 7 Dec 2016 09:52:32 -0500 (EST) Received: by mail-io0-f200.google.com with SMTP id t31so287730158ioi.4 for ; Wed, 07 Dec 2016 06:52:32 -0800 (PST) Received: from resqmta-ch2-06v.sys.comcast.net (resqmta-ch2-06v.sys.comcast.net. [2001:558:fe21:29:69:252:207:38]) by mx.google.com with ESMTPS id v126si17550994ioe.252.2016.12.07.06.52.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 07 Dec 2016 06:52:31 -0800 (PST) Date: Wed, 7 Dec 2016 08:52:27 -0600 (CST) From: Christoph Lameter Subject: Re: [PATCH] mm: page_alloc: High-order per-cpu page allocator v7 In-Reply-To: <20161207101228.8128-1-mgorman@techsingularity.net> Message-ID: References: <20161207101228.8128-1-mgorman@techsingularity.net> Content-Type: text/plain; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , Michal Hocko , Vlastimil Babka , Johannes Weiner , Jesper Dangaard Brouer , Joonsoo Kim , Linux-MM , Linux-Kernel On Wed, 7 Dec 2016, Mel Gorman wrote: > SLUB has been the default small kernel object allocator for quite some time > but it is not universally used due to performance concerns and a reliance > on high-order pages. The high-order concerns has two major components -- SLUB does not rely on high order pages. It falls back to lower order if the higher orders are not available. Its a performance concern. This is also an issue for various other kernel subsystems that really would like to have larger contiguous memory area. We are often seeing performance constraints due to the high number of 4k segments when doing large scale block I/O f.e. Otherwise I really like what I am seeing here. -- 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