From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 30 Mar 2003 10:28:04 +0200 From: Boris Bezlaj To: Paul Mackerras Cc: linuxppc-dev@lists.linuxppc.org Subject: Re: 2.4.x swim3 performance problem on PM4400 identified Message-ID: <20030330082804.GA495@gajba.net> References: <16004.27866.270601.561756@gargle.gargle.HOWL> <16005.35950.570218.844672@nanango.paulus.ozlabs.org> <20030329155501.GA587@gajba.net> <16006.19831.210218.170305@nanango.paulus.ozlabs.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <16006.19831.210218.170305@nanango.paulus.ozlabs.org> Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Sun, Mar 30, 2003 at 11:50:47AM +1000, Paul Mackerras wrote: > Boris Bezlaj writes: > > > | kista:/tmp# dd if=swimmer of=/dev/fd0 bs=512 count=2880 > > | swim3: timeout reading sector 2647 > > Hmmm, wonder why it's reading that sector? > > The timeout probably indicates that the sector header is corrupted or > unreadable. The driver should probably retry after verifying that it > is on the right track. Well it is the _bad_ floppy case :) > > | end_request: I/O error, dev 02:00 (floppy), sector 2647 <--bad sector > > | dd: writing `/dev/fd0': Input/output error > > | 2647+0 records in > > | 2646+0 records out > > | 1354752 bytes transferred in 134.614549 seconds (10064 bytes/sec) > > > > after the error at sector 2647, swim3 seems to move the heads to sector 0 > > and write? another 2647 sectors. Any particular reason for that ? > > I don't think it's the swim3 driver itself that is doing that. I > would start by stracing the dd to see what writes it is doing. It may > be the block I/O layer doing something funny. I will give it a shot later in the evening. Many thanks for your effort 8) -- Boris ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/