From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 45D736B009A for ; Tue, 12 May 2009 13:21:07 -0400 (EDT) Received: from localhost (smtp.ultrahosting.com [127.0.0.1]) by smtp.ultrahosting.com (Postfix) with ESMTP id 494FF82CDF8 for ; Tue, 12 May 2009 13:33:59 -0400 (EDT) Received: from smtp.ultrahosting.com ([74.213.175.254]) by localhost (smtp.ultrahosting.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id CzQuBB49NWJv for ; Tue, 12 May 2009 13:33:59 -0400 (EDT) Received: from qirst.com (unknown [74.213.171.31]) by smtp.ultrahosting.com (Postfix) with ESMTP id 4B94282CE02 for ; Tue, 12 May 2009 13:33:35 -0400 (EDT) Date: Tue, 12 May 2009 17:20:02 -0400 (EDT) From: Christoph Lameter Subject: Re: [PATCH -mm] vmscan: protect a fraction of file backed mapped pages from reclaim In-Reply-To: <4A09AC91.4060506@redhat.com> Message-ID: References: <20090508125859.210a2a25.akpm@linux-foundation.org> <20090512025246.GC7518@localhost> <20090512120002.D616.A69D9226@jp.fujitsu.com> <4A09AC91.4060506@redhat.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Rik van Riel Cc: KOSAKI Motohiro , Wu Fengguang , Andrew Morton , "hannes@cmpxchg.org" , "peterz@infradead.org" , "linux-kernel@vger.kernel.org" , "tytso@mit.edu" , "linux-mm@kvack.org" , "elladan@eskimo.com" , "npiggin@suse.de" , "minchan.kim@gmail.com" List-ID: On Tue, 12 May 2009, Rik van Riel wrote: > The patch that only allows active file pages to be deactivated > if the active file LRU is larger than the inactive file LRU should > protect the working set from being evicted due to streaming IO. Streaming I/O means access once? What exactly are the criteria for a page to be part of streaming I/O? AFAICT the definition is more dependent on the software running than on a certain usage pattern discernible to the VM. Software may after all perform multiple scans over a stream of data or go back to prior locations in the file. -- 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