[OpenAFS] cache managers on openAFS clients NOT caching

Derrick J Brashear shadow@dementia.org
Thu, 30 Sep 2004 12:16:06 -0400 (EDT)

You seem to have done a lot off stuff entirely other than what he asked 
you to do.

On Thu, 30 Sep 2004, Kristian wrote:

> At this point I closed firefox and stopped the cache manager... then
> started it up again leaving the cache untouched. Most surprisingly if I
> issue the same cmdebug command, all the callbacks are gone. If I

That's not shocking at all.

> remember correctly, the cache manager doesn't fetch files from the AFS
> server if the file's callback is still valid! If the callbacks aren't
> there upon restart, the cache manager is definitely doing the right
> thing,


> which is fetching the files from the server.

No. If it already had the correct fid/uniquifier in the cache it shouldn't 
refetch. It should restat the file, though. That's necessary to confirm 
you still have the correct data.

On your server, get modern tcpdump.
tcpdump -s 1500 -vv host (clientname) and port 7001

the interesting thing is fetchdata. what do you see?

> 	1) how can I extend the validity of a callback? I would actually
> 	   like to configure my cell to serve read-only files with
> 	   unlimited expiration time... callbacks should be broken
> 	   by the server ONLY when changes are released.

Callbacks weren't broken by the server. You gave them back when you 
stopped the cache manager. It's better than having a fileserver trying to 
break callbacks to a client which isn't online. No, we won't "fix it", 
because it's not broken.

> 	2) is it possible to configure the cache managers to keep
> 	   track of all the callbacks stored even after a restart?

See above.