Slow LIST command

[Jeremy Rumpf]

> Cyrus doesn't do anything to increase the BDB cache
> size, and the default (256 kB) is way too small for any reasonably large
> site. With some 50000 mailboxes and random operations, I found the hit rate
> for default BDB cache to be 70-80%. After growing the cache size to 2M, hit
> rate approached 99% and disk traffic was greatly reduced since most of the
> operations are reads anyway. Therefore processes could complete their work
> and release their locks much more quickly, and the dreaded "DBERROR: xxx
> lockers" messages stayed at a comfortable level.
>

Out of sheer curiosity. I'm assuming the skiplist backend also uses an in core 
cache as well? If so, is it also tuneable or does it dynamically extend 
itself?

Cheers,
Jeremy