"lmtpunix[32741]: DBERROR db4: 474 lockers"

[Ciprian Vizitiu]

Hi everybody,

Early this morning a Cyrus  2.2.12 running on a RHEL 4 started refusing 
delivery under the reason(s):

lmtpunix[30668]: DBERROR db4: Logging region out of memory; you may need 
to increase its size
lmtpunix[30668]: DBERROR: opening /var/lib/imap/deliver.db: Cannot 
allocate memory
lmtpunix[30668]: DBERROR: opening /var/lib/imap/deliver.db: cyrusdb error
lmtpunix[30668]: FATAL: lmtpd: unable to init duplicate delivery database

Being hard pressed I've simply restarted the server and... uh, it works. 
Later on (some 1 h) the log started showing increasing numbers of  
"lmtpunix[32741]: DBERROR db4: XYZ lockers" with XYZ steady increasing.

How do I increase the "Logging region"? And what's the meaning of the 
DB4 lockers in this context? Any hints on decreasing them? =:-o