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Re: attn: ghudson; FSFS and multi-threading on Unix broken?

From: Mark Phippard <MarkP_at_softlanding.com>
Date: 2005-04-07 19:46:51 CEST

Greg Hudson <ghudson@MIT.EDU> wrote on 04/07/2005 01:38:06 PM:

> > Didn't someone else point out that this problem would not exist on
Linux
> > prior to the 2.6 kernel? That could explain why it hasn't shown up.
>
> I doubt it. Red Hat kernels have used NPTL for quite a while now, and
> that's a pretty popular platform.

In terms of typical *nix usage, I assume that file:// and svn+ssh:// would
be immune to the problem since concurrent access would occur in different
processes.

I believe someone said that the svnserve daemon will fork a process unless
you run it with the --threads option. So, in "process" mode it would also
be immune.

That leave us with mod_dav_svn. Does Apache on *nix always/typically use
threads? AFAIK, the answer to that is yes, but I primarily only use
Windows and OS/400 so do not really know.

I am just trying to get to the bottom of why this problem might not have
surfaced. Are there any *nix/BSD platforms where fcntl() locks to a
thread instead of a process, as apparently Linux did prior to NPTL?

Mark

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Received on Thu Apr 7 19:47:48 2005

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