Dbtmpdir Option

The  Message Store option specifies the mailbox list database temporary directory. Defaults to, where    is composed of mail server user plus the $SERVERROOT with   replaced by   e.g.

This is a directory which is very heavily accessed. If the disks that house the mboxlist database temporary directory are not fast enough at very large sites, performance problems might occur. As part of their performance and tuning steps, sites should take a note of this and define a value for this parameter which either points to a memory mapped file system, or which points to a location on a fast file system.

See also:
 * Message Store options