Coda File System

Re: write failure issues

From: Jan Harkes <jaharkes_at_cs.cmu.edu>
Date: Wed, 19 May 2004 00:13:41 -0400
On Tue, May 18, 2004 at 01:00:55PM +0200, Johannes Martin wrote:
> On Mon, 17 May 2004 shivers_at_cc.gatech.edu wrote:
> > While on the topic of mysterious error msgs, note the last line of this
> > cfs output:
> >
> >     % cfs lv ~/c
> >       Status of volume 0x7f000000 (2130706432) named "coda:root"
> >       Volume type is ReadWrite
> >       Connection State is WriteDisconnected
> >       Minimum quota is 0, maximum quota is unlimited
> >       Current blocks used are 6385968
> >       The partition has 122675704 blocks available out of 129111892
> >       Write-back is VIOC_STATUSWB: Invalid argument
> >
> > Vas ist das "VIOC_STATUSWB: Invalid argument" write-back mode?
> > I'm running the 6.0.6 client.
> 
> I get that message, too, but only occasionally.

Never seen that myself, I've only seen 'Write-back is disabled'.

(Writeback caching was an experiment to get write-disconnected mode
performance with connected mode semantics. It doesn't work too well
because the write-disconnected client is constantly forced to
reintegrate when other clients are revalidating their cache where they
try to get the writeback permit, which is then invalidated, ad
infinitum. I've mostly removed the writeback related code from the
servers, only some stubs are left.)

When that writeback status ioctl returns an error, cfs exits. And this
happens a couple of lines before we print whether there are any pending
conflicts or CML entries in the volume. So getting that error actually
hides some possibly useful information.

Jan
Received on 2004-05-19 00:18:12