followup: stuck lmtpd processes

[Andrew Morgan]

On Wed, 24 Sep 2003, John Wade wrote:

> The patch I wrote still might help you since it would prevent an
> individual user's problem from taking down the mail system.   The user's
> mailbox would remain inaccessible, but the lmtpd processes attempting
> delivery would exit with errors and mail delivery as a whole would
> proceed.     I still belive that a system with that uses locking with no
> timeout mechanism is inherently fragile.  A single programming error can
> lead to a cascade failure that takes down the entire mail system as more
> and more processes hang up trying to get the lock.

In this case, the problem only affected a single user.  Anything that
tried to get a lock on that user's quota file hung.  I had a lot of lmtpd
processes hung waiting for the lock, but that didn't really impact the
system.  The other users of the system were unaffected.

I'm not saying it is acceptable, but the impact was minor.

	Andy