From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta7.messagelabs.com (mail6.bemta7.messagelabs.com [216.82.255.55]) by kanga.kvack.org (Postfix) with ESMTP id 67F676B01F5 for ; Fri, 14 Oct 2011 10:19:24 -0400 (EDT) Date: Fri, 14 Oct 2011 09:19:21 -0500 From: Dimitri Sivanich Subject: Re: [PATCH] Reduce vm_stat cacheline contention in __vm_enough_memory Message-ID: <20111014141921.GC28592@sgi.com> References: <20111012120118.e948f40a.akpm@linux-foundation.org> <20111013152355.GB6966@sgi.com> <20111013135032.7c2c54cd.akpm@linux-foundation.org> <20111013142434.4d05cbdc.akpm@linux-foundation.org> <20111014122506.GB26737@sgi.com> <20111014135055.GA28592@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Mel Gorman On Fri, Oct 14, 2011 at 08:57:16AM -0500, Christoph Lameter wrote: > On Fri, 14 Oct 2011, Dimitri Sivanich wrote: > > > Testing on a smaller machine with 46 writer threads in parallel (my original > > test used 120). > > > > Looks as though cache-aligning and padding the end of the vm_stat array > > results in a ~150 MB/sec speedup. This is a nice improvement for only 46 > > writer threads, though it's not the full ~250 MB/sec speedup I get from > > setting OVERCOMMIT_NEVER. > > Add to this the increase in the deltas for the ZVCs and change the stat > interval to 10 sec? Increasing the ZVC deltas (threshold value in calculate*threshold == 125) does -seem- to give a small speedup in this case (maybe as much as 50 MB/sec?). Changing the stat interval to 10 seconds still has no effect, with or without the ZVC delta change. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org