[OpenAFS] Puzzler: lack of access to AFS files

Rodney M. Dyer rmdyer@uncc.edu
Mon, 17 Dec 2007 16:07:59 -0500


At 03:12 PM 12/17/2007, Jeffrey Altman wrote:
>That is not true at all.   If the CIFS interface reads 64KB at a time
>and refuses to request the next 64KB until the previous one has been
>delivered and the CM is reading 1MB at a time, then there is significant
>overhead caused by the CIFS interface.  Why should I lose hundreds of
>microseconds per 64KB simply because the CIFS protocol is dumb?

I believe you, I was just wondering aloud.

>You wouldn't do file caching in the file server.  you would perform
>block caching.   I'm not going to cache a 250GB file, I'm going to cache
>that parts of the file that have been used recently.

True.

> > Not always.  The previous error mentioned in the last message was from
> > just such a volume.
>
>Then file a bug report because otherwise I have no idea I should be 
>looking for issues.

The error mentioned is random enough that tracking it down just leads to a 
can of worms that involves routers/switches/packets/server 
logs/etc.  Filing bug reports for non-repeatable errors is kind of shooting 
in the dark.

It's a cost benefit problem.  For this error, I won't say anymore about it 
until it impacts me to the point of being intolerable.

Rodney