[OpenAFS-devel] Bug with OpenAFS memory-mapped file I/O under Linux

[Hartmut Reuter]

chas williams wrote:
> 
> >We've run into a rather annoying issue here while running tests on Openafs
> >1.2.2 on Redhat 7.0 (using the 2.4.9-12 kernel).  Maybe someone on the list
> >is familiar with the problem or has a suggestion.
> 
> any chance you could do a 'fstrace setset -active', run your test code,
> 'fstrace dump' and send the result output?  that would be somewhat
> useful.

I could reproduce the problem here, but as soon as I do the same with
fstrace switched on the program lets panic my machine. So there must be
some bad operand to an afs_Tracex() call. 

Harmtut


> 
> >BTW, earlier Redhat kernels had a similar problem under NFS, but it's fixed
> >in 2.4.9-12 and later.
> 
> a quick search on the net shows that the following patch fixed the nfs problem:
> 
> http://www.fys.uio.no/~trondmy/src/2.4.7/linux-2.4.7-mmap.dif
> 
> it looks the big change was to cache the rpc credentials with the file.
> i suppose its possible that the write/close for mmap is being handled by an
> anonymous thread.  (irix does this somewhat)
> _______________________________________________
> OpenAFS-devel mailing list
> OpenAFS-devel@openafs.org
> https://lists.openafs.org/mailman/listinfo/openafs-devel

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Hartmut Reuter                           e-mail reuter@rzg.mpg.de
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Computing Center of the Max-Planck-Gesellschaft (MPG) and the
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