Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751670Ab0DYHOX (ORCPT ); Sun, 25 Apr 2010 03:14:23 -0400 Received: from ksp.mff.cuni.cz ([195.113.26.206]:53831 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751038Ab0DYHOV (ORCPT ); Sun, 25 Apr 2010 03:14:21 -0400 Date: Sun, 25 Apr 2010 09:13:49 +0200 From: Pavel Machek To: Mikulas Patocka Cc: linux-kernel@vger.kernel.org, linux-mm@vger.kernel.org Subject: Re: swapping when there's a free memory Message-ID: <20100425071349.GA1275@ucw.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1145 Lines: 30 Hi! > I captured this output of vmstat. The machine was freeing cache and > swapping out pages even when there was a plenty of free memory. > > The machine is sparc64 with 1GB RAM with 2.6.34-rc4. This abnormal > swapping happened during running spadfsck --- a fsck program for a custom > filesystem that caches most reads in its internal cache --- so it reads > buffers and allocates memory at the same time. > > Note that sparc64 doesn't have any low/high memory zones, so it couldn't > be explained by filling one zone and needing to allocate pages in it. Fragmented memory + high-order allocation? > This abnormal behavior doesn't happen everytime, it happend about twice > for many spadfsck attempts. ...yep, that would be random. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/