Coda File System

Re: Codafilesystem crashes after parallel write access to different Files

From: Jan Harkes <jaharkes_at_cs.cmu.edu>
Date: Thu, 27 Apr 2006 16:12:05 -0400
On Thu, Apr 27, 2006 at 06:09:15PM +0200, Marcel Kossin wrote:
> If I create many small (about 50KB) different files on a
> Codafilesystem in the same Directory in parallel the Codaserver won't
> respond anymore after writing 4 or 5 files.

I don't really see how there could be a problem. Our userspace cache
manager only sees open and close operations, so the individual writes
are going directly to the underlying filesystem where the cached files
are stored.

Then when the file is closed, an upcall is queued for venus, the
queueing in the kernel (as well as the volume locks that is taken in
userspace) will effectively serialize all those close operations.

Are you sure your client isn't simply going into write-disconnected mode?

In any case, run 'codacon', it will show a lot of more transient
messages that are not logged to logfiles which will be helpful in
determining what the client is doing.

You can also check volume status with 'cfs lv /coda/path/to/volume' this
will, amongst other things, show connectivity status of the volume.

Jan
Received on 2006-04-27 16:13:58