From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Date: Sun, 20 Jan 2008 20:02:22 +0000 Subject: Re: blktrace & btrace usability Message-Id: <20080120200222.GA6258@kernel.dk> List-Id: References: <47906577.8090604@tlinx.org> In-Reply-To: <47906577.8090604@tlinx.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-btrace@vger.kernel.org On Fri, Jan 18 2008, Linda Walsh wrote: > Jens Axboe wrote: > >On Fri, Jan 18 2008, Linda Walsh wrote: > > > >>I was examining the SuSE10.3 boot process and noted > >>it is setup to start & stop blktrace while the system > >>is booting. Odd think is that it checks to verify that > >>the root file system is of type "ext3". > >> > >>Is that a "SuSEism" or is there some reason why it wouldn't > >>work with any file system? > >> > > > >Interesting, I never noticed that before. Don't know why they check for > >ext3, perhaps their post processing tools map blocks to files and only > >works for ext3? > > > --- > Would be nice if they left a comment to that effect. > ext2 should be the same, and I think xfs has all the > data needed to process it under a perl script -- xfs_bmap, > for example, prints off all of the blocks used by a file (so > it's easy to compute fragmentation). > > They don't seem to include a util in the blktrace package > to map blocks to to files. Anyway, you answer my question -- > blktracing doesn't rely on something ext3 specific. There's definitely nothing fs specific in blktrace. IIRC, Olaf Kirch wrote something called fsmap while at SUSE. Perhaps that is a clue to what they are doing there? -- Jens Axboe