[OpenAFS] write caching differences between 1.2 and 1.4 clients?

Jeffrey Altman jaltman@secure-endpoints.com
Tue, 14 Aug 2007 14:44:16 -0400


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Stephan.Wiesand@desy.de wrote:
>
> That's bad news. I believe we're experiencing right now that it does
> limit concurrent writes to files in the same directory from our farm
> nodes. I guess it will also cause a higher degree of fragmentation of
> files on the fileserver, and probably make things more "NFS-like" in
> general.

Writing to a file does not invalidate the status information on the
directory that contains it.  If you have multiple clients
reading/writing the same file, then you will have contention issues.

What store behind mode does is produce more RPC requests to the file server.

> Any chance to get back the old behaviour?

There is always a chance.  The questions are what is broken and why did
it break when Linux 2.6 support was added.  Someone will have to debug
the actual problem versus the observed symptom.





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