On Thursday 06 January 2011 01:45:00 Victor Duchovni wrote: > On Wed, Jan 05, 2011 at 06:56:31PM -0500, Wietse Venema wrote: > > Each verify or postscreen or tlsmgr process will at set times > > scan the database for old entries. > > > > If it so happens that this scan doesn't finish before the new one > > starts, then it would really be a W*T*F* moment if the code decides > > that the new scan completes immediately, especially if it means > > that the old scan is stopped too. > > When the Postfix queue-manager is scanning the incoming or deferred queue, > if another scan request comes in in the middle of an existing scan, the > exsting scan continues, but a flag is set (idempotent) that indicates > that a new scan should start as soon as the old scan completes. > > In this case, it is not as critical to set such a flag, but it is important > to allow the existing scan to continue to completion, and ignore or > (just note) new requests until it does. Once a scan completes, new > scans can proceed either immediately (saved flag) or when next requested.
That's what I have implemented. If a cleanup process is already running and a second cleanup process starts then the second process will quit as if the database was empty and it will log a warning that the cleanup was skipped due to an already running process. The first cleanup process will continue and complete the database scan. A subsequent cleanup process will start as scheduled. I don't use a flag to put a simultaneously running cleanup process on hold, it will just be skipped. And that shouldn't be a problem because the cleanup process isn't a time critical process. I'm sorry for the confusion. regards Stefan
