From: Theodore Tso Subject: Re: Question on block group allocation Date: Mon, 27 Apr 2009 18:40:52 -0400 Message-ID: <20090427224052.GC22104@mit.edu> References: <6601abe90904230941x5cdd590ck2d51410326df2fc5@mail.gmail.com> <20090423190817.GN3209@webber.adilger.int> <6601abe90904231502y393155dbrf8913b728c704320@mail.gmail.com> <20090427021411.GA9059@mit.edu> <6601abe90904262229w602e17d8s51ceae05c2895ce5@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andreas Dilger , ext4 development To: Curt Wohlgemuth , G@mit.edu Return-path: Received: from thunk.org ([69.25.196.29]:38600 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752383AbZD0Wk7 (ORCPT ); Mon, 27 Apr 2009 18:40:59 -0400 Content-Disposition: inline In-Reply-To: <6601abe90904262229w602e17d8s51ceae05c2895ce5@mail.gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sun, Apr 26, 2009 at 11:29:39PM -0600, Curt Wohlgemuth wrote: > The random read throughput on the 10GB file went from ~16 MB/s to ~22 > MB/s after Andreas' patch; the total fragmentation of the file was > much lower than before his patch. > > However, the number of extents went up by quite a bit (I don't have > the debugfs output in front of me at the moment, sorry). I'm curious what you meant by the combination of these two statements, "the total fragmentation of the file was much lower than before his patch", and "the number of extents went up by quite a bit". Can you send me the debugfs output when you have a chance? Thanks, - Ted