From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e2.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id l2EKtgl4000560 for ; Wed, 14 Mar 2007 16:55:42 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l2EKtgTD314990 for ; Wed, 14 Mar 2007 16:55:42 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l2EKtgPb032023 for ; Wed, 14 Mar 2007 16:55:42 -0400 Subject: Re: [PATCH] mm/filemap.c: unconditionally call mark_page_accessed From: Dave Kleikamp In-Reply-To: References: <20070312142012.GH30777@atrey.karlin.mff.cuni.cz> <20070312143900.GB6016@wotan.suse.de> <20070312151355.GB23532@duck.suse.cz> <20070312173500.GF23532@duck.suse.cz> <20070313185554.GA5105@duck.suse.cz> Content-Type: text/plain Date: Wed, 14 Mar 2007 15:55:41 -0500 Message-Id: <1173905741.8763.36.camel@kleikamp.austin.ibm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Ashif Harji Cc: linux-mm@kvack.org, Nick Piggin , Jan Kara , linux-kernel@vger.kernel.org, akpm@linux-foundation.org List-ID: On Wed, 2007-03-14 at 15:58 -0400, Ashif Harji wrote: > This patch unconditionally calls mark_page_accessed to prevent pages, > especially for small files, from being evicted from the page cache despite > frequent access. I guess the downside to this is if a reader is reading a large file, or several files, sequentially with a small read size (smaller than PAGE_SIZE), the pages will be marked active after just one read pass. My gut says the benefits of this patch outweigh the cost. I would expect real-world backup apps, etc. to read at least PAGE_SIZE. Shaggy -- David Kleikamp IBM Linux Technology Center -- 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