mupdate cpu, thread timeouts

[Wesley Craig]

On 01 Jul 2010, at 15:25, John Madden wrote:
> Lately, I've been seeing a lot of this from imap frontends, repeating
> over and over:

These:

> Jul  1 15:16:51 imap mupdate[18204]: Thread timed out waiting for
> listener_lock
> Jul  1 15:16:51 imap mupdate[18204]: Worker thread finished, for a  
> total
> of 4 (3 spare)
> Jul  1 15:16:51 imap mupdate[18204]: Thread timed out waiting for
> listener_lock
> Jul  1 15:16:51 imap mupdate[18204]: Worker thread finished, for a  
> total
> of 3 (3 spare)
> Jul  1 15:16:51 imap mupdate[18204]: Thread timed out waiting for
> listener_lock
> Jul  1 15:16:51 imap mupdate[18204]: Worker thread finished, for a  
> total
> of 2 (2 spare)

> Jul  1 15:16:52 imap mupdate[18206]: New worker thread started, for a
> total of 1
> Jul  1 15:16:52 imap mupdate[18206]: New worker thread started, for a
> total of 2
> Jul  1 15:16:52 imap mupdate[18206]: New worker thread started, for a
> total of 3
> Jul  1 15:16:52 imap mupdate[18206]: New worker thread started, for a
> total of 4
> Jul  1 15:16:52 imap mupdate[18206]: New worker thread started, for a
> total of 5

are not interesting.  I might say spurious.  They reflect that the  
mupdate on this machine starts 5 worker threads, and needs none.  These:

> Jul  1 15:15:52 imap mupdate[18206]: unready for connections
> Jul  1 15:15:52 imap mupdate[18206]: synchronizing mailbox list with
> master mupdate server
> Jul  1 15:16:51 imap mupdate[18206]: mailbox list synchronization  
> complete
> Jul  1 15:16:54 imap mupdate[18203]: unready for connections
> Jul  1 15:16:54 imap mupdate[18203]: synchronizing mailbox list with
> master mupdate server


are the interesting messages.  It says to me that the connection to  
the mupdate master is being lost.  However, there ought to be an  
error message to that effect, which I don't see.  What's happening on  
the mupdate master?

> Also during this time, mailbox changes (CREATE/etc)
> are delayed or timeout.

That's normal, as the mupdate master blocks changes while a frontend  
is synchronizing.

:wes