Re: back-bdb cache and back-monitor

["Pierangelo Masarati" <ando@sys-net.it>]

> Is there any thought to developing (or is there already and I've missed
> it) a way to see if the cachesize (as specified in slapd.conf) is
> sufficient for the workload?  What I'm thinking of is a query to the
> back-monitor which would return the cache hit/miss numbers.  Is that
> possible?  Are they even calculated?

Currently, this is not possible.  I haven't looked at it in detail, but I
think there should not be any relevant technical problem.  However, let me
repeat that I haven't looked ad back-bdb's cache close enough to state
this for sure, nor I'm committing to looking at it :).

Currently, there's some work on back-monitor that should make it easy, by
allowing external code to register and update entries in back-monitor. 
back-bdb could exploit this by registering a "cn=Cache" entry under each
database instance of the bdb backend and registering a callback that, upon
monitor entry read request, updates the desired figure by referencing the
data stored in back-bdb itself.  Then, it's just a matter of recording the
desired figures, with appropriate concurrency protection.

p.

-- 
Pierangelo Masarati
mailto:pierangelo.masarati@sys-net.it


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