From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kalpak Shah Subject: Re: ChunkFS - measuring cross-chunk references Date: Mon, 23 Apr 2007 15:04:36 +0530 Message-ID: <1177320876.23226.7.camel@garfield> References: <2e4afe1e0704221335y6d4c84d8id65e71826ce60acb@mail.gmail.com> <462B8D0C.7020509@ksu.edu> <2e4afe1e0704230019h3853bc82uae6c9b5cdc325ab9@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Amit Gud , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Karuna sagar K Return-path: Received: from svr68.ehostpros.com ([67.15.48.48]:26398 "EHLO svr68.ehostpros.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161398AbXDWLNs (ORCPT ); Mon, 23 Apr 2007 07:13:48 -0400 In-Reply-To: <2e4afe1e0704230019h3853bc82uae6c9b5cdc325ab9@mail.gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Mon, 2007-04-23 at 12:49 +0530, Karuna sagar K wrote: > Hi, > > The tool estimates the cross-chunk references from an extt2/3 file > system. It considers a block group as one chunk and calcuates how many > block groups does a file span across. So, the block group size gives > the estimate of chunk size. > > The file systems were aged for about 3-4 months on a developers laptop. > With a blocksize of 4KB, a block group would be 128 MB. In the original Chunkfs paper, Valh had mentioned 1GB chunks and I believe it will be possible to use 2GB, 4GB or 8GB chunks in the future. As the chunk size increases the number of cross-chunk references will reduce and hence it might be a good idea to present these statistics considering different chunk sizes starting from 512MB upto 2GB. Thanks, Kalpak.