From: KOSAKI Motohiro Subject: Re: tracepoints in ext4 (and/or ext3?) Date: Tue, 12 Aug 2008 15:33:02 +0900 Message-ID: <20080812152113.9470.KOSAKI.MOTOHIRO@jp.fujitsu.com> References: <48A09E7F.7060605@redhat.com> <20080812032335.GC21194@mit.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Cc: kosaki.motohiro@jp.fujitsu.com, Eric Sandeen , ext4 development To: Theodore Tso Return-path: Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:55895 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751275AbYHLGd6 (ORCPT ); Tue, 12 Aug 2008 02:33:58 -0400 In-Reply-To: <20080812032335.GC21194@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: > On Mon, Aug 11, 2008 at 03:18:07PM -0500, Eric Sandeen wrote: > > As just an initial inquiry, I'm wondering how people would feel about > > putting some tracepoints (trace_mark()) into ext[34] for monitoring the > > fs behavior. > > I think it's a great idea! Do you have some specific tracepoints in > mind? I think two viewpoint exist. An administrator want to - performance mesurement - which IO aborted it, if any error happend. In addition, OS vendor want to - split out fs problem and device problem So, candidate of tracepints are - jbd activity - boundary activity between fs and block layer I don't fs expert, it is just idea.