From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx198.postini.com [74.125.245.198]) by kanga.kvack.org (Postfix) with SMTP id 6F6296B0007 for ; Mon, 28 Jan 2013 18:03:06 -0500 (EST) Date: Mon, 28 Jan 2013 15:03:04 -0800 From: Andrew Morton Subject: Re: [PATCH 1/11] ksm: allow trees per NUMA node Message-Id: <20130128150304.2e7a2fb4.akpm@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Hugh Dickins Cc: Petr Holasek , Andrea Arcangeli , Izik Eidus , Rik van Riel , David Rientjes , Anton Arapov , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Fri, 25 Jan 2013 17:54:53 -0800 (PST) Hugh Dickins wrote: > --- mmotm.orig/Documentation/vm/ksm.txt 2013-01-25 14:36:31.724205455 -0800 > +++ mmotm/Documentation/vm/ksm.txt 2013-01-25 14:36:38.608205618 -0800 > @@ -58,6 +58,13 @@ sleep_millisecs - how many milliseconds > e.g. "echo 20 > /sys/kernel/mm/ksm/sleep_millisecs" > Default: 20 (chosen for demonstration purposes) > > +merge_across_nodes - specifies if pages from different numa nodes can be merged. > + When set to 0, ksm merges only pages which physically > + reside in the memory area of same NUMA node. It brings > + lower latency to access to shared page. Value can be > + changed only when there is no ksm shared pages in system. > + Default: 1 > + The explanation doesn't really tell the operator whether or not to set merge_across_nodes for a particular machine/workload. I guess most people will just shrug, turn the thing on and see if it improved things, but that's rather random. -- 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