Is using Berkeley DB 4.0.14 recommended?

[Aidan Evans]

On Wed, 23 Oct 2002 at 15:55 Aidan Evans wrote to Info Cyrus, Rob...

>On Sat, 19 Oct 2002 at 10:49 Rob Siemborski wrote to Aidan Evans and Info Cyrus
>
>>On Sat, 19 Oct 2002, Aidan Evans wrote:
>...
>>>   My experience with DB 4.0.14 on RedHat Linux 7.2 is two instances of
>>> complete failure of deliver.db and tls_sessions.db (and consequently all
>>> Sieve processing) when the number of lockers reached 50,000, both instances
>>> after about a week to ten days up time.  I expect a third failure if I let
>>> the number of lockers get that high again.
>>
>>I don't think I've ever seen numbers that high, so I can't comment.
>
>  Does CMU have a regular Cyrus shutdown/restart and/or regular reboot of
>the machine running Cyrus?  Rebooting certainly resets the lock count; I
>don't know if just a Cyrus restart is enough but I suspect not.

  The issue of the number of lockers growing without bounds has been
resolved.  Back in September when we were having connection problems
(client takes minutes to get asked for the username), which eventually were
solved by turning on asynchronous syslogging, I surmised that there might
be a problem with re-use of processes by Cyrus on Linux and changed MAX_USE
in service.h to 1 (was 250).  This seemed to help but I think in retrospect
it was an illusion.

  The change to MAX_USE was left in even after syslogging was changed.  A
couple of weeks ago I recalled this and it occurred then to me that maybe
the lack of process re-use was what was causing the number of lockers to
grow so fast (300 to 500 per hour, so the 50,000 limit would be reached in
less than a week resulting in a corrupt deliver.db and tls_sessions.db).
I've put MAX_USE back to the standard 256.  It's been nearly four days
since our most recent restart of Cyrus and "Maximum number lockers so far"
out of "db_stat -c" is just 374.  At this rate Cyrus can stay up for over a
year without running out of locks.

Aidan Evans   | Networks & Systems
(902)494-3332 | University Computing & Information Services
              | Dalhousie University, Halifax, N.S., Canada