Subject: Re: Simultaneous builds
To: Manuel Bouyer <>
From: David Maxwell <>
List: tech-pkg
Date: 01/11/2002 16:14:45
On Fri, Jan 11, 2002 at 06:55:59PM +0100, Manuel Bouyer wrote:
> On Fri, Jan 11, 2002 at 06:39:49PM +0100, Martin Weber wrote:
> > BUGS
> >      Does not work on NFS or other network filesystem on different systems be-
> >      cause the disparate systems have disjoint PID spaces.
> Ha yes, but this is because shlock tries to ping the process and
> can't do it if it's on another host. It's not because a NFS issue.
> What we could do is have shlock record the name of the host in
> addition to the pid, and skip the pid check if the host name is different
> (just fail).

Ahh. Well, when I originally wrote that PR, I was only trying to solve
the issue of multiple builds on a single host.

One option would be to consider shlock to be overkill - it probably
isn't neccessary to eliminate the race condition between simultaneous
grabs of a pkgsrc dir. Eliminating the clobber might be enough - use a
simple lockfile with a single name to indicate that the directory is in
use, so a new process doesn't start using a dir that's being worked in.

Any NFS use would leave the problem of stale locks though - there's no
simple cross-platform way I know of to test for another NFS client
holding a filehandle.

David Maxwell,| -->
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