From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id A94526B0011 for ; Thu, 28 Apr 2011 09:32:16 -0400 (EDT) Date: Thu, 28 Apr 2011 15:31:55 +0200 From: Pavel Machek Subject: Re: [PATCH 00/13] Swap-over-NBD without deadlocking Message-ID: <20110428133154.GA8572@ucw.cz> References: <1303803414-5937-1-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1303803414-5937-1-git-send-email-mgorman@suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Linux-MM , Linux-Netdev , LKML , David Miller , Neil Brown , Peter Zijlstra Hi! > For testing swap-over-NBD, a machine was booted with 2G of RAM with a > swapfile backed by NBD. 16*NUM_CPU processes were started that create > anonymous memory mappings and read them linearly in a loop. The total > size of the mappings were 4*PHYSICAL_MEMORY to use swap heavily under > memory pressure. Without the patches, the machine locks up within > minutes and runs to completion with them applied. > > Comments? Nice! It is easy to see why swapping needs these fixes, but... dirty memory writeout is used for memory clearing, too. Are same changes neccessary to make that safe? (Perhaps raise 'max dirty %' for testing?) Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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