From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx161.postini.com [74.125.245.161]) by kanga.kvack.org (Postfix) with SMTP id 06F3C6B002C for ; Wed, 1 Feb 2012 04:18:15 -0500 (EST) Date: Wed, 1 Feb 2012 04:18:07 -0500 From: Christoph Hellwig Subject: Re: [PATCH] fix readahead pipeline break caused by block plug Message-ID: <20120201091807.GA7451@infradead.org> References: <1327996780.21268.42.camel@sli10-conroe> <20120131220333.GD4378@redhat.com> <20120131141301.ba35ffe0.akpm@linux-foundation.org> <20120131222217.GE4378@redhat.com> <20120201033653.GA12092@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120201033653.GA12092@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Vivek Goyal Cc: Andrew Morton , Shaohua Li , lkml , linux-mm , Jens Axboe , Herbert Poetzl , Eric Dumazet , Wu Fengguang On Tue, Jan 31, 2012 at 10:36:53PM -0500, Vivek Goyal wrote: > I still see that IO is being submitted one page at a time. The only > real difference seems to be that queue unplug happening at random times > and many a times we are submitting much smaller requests (40 sectors, 48 > sectors etc). This is expected given that the block device node uses block_read_full_page, and not mpage_readpage(s). -- 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