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Re: ACL optimization

--On Thursday, August 04, 2005 7:42 PM +0200 "Josà M. FandiÃo" <ldap@fadesa.es> wrote:

Aside from ACL's, another thing to look at is your idlcache.  Since you
didn't post what your idlcache/cachesize settings were for the OpenLDAP
server, it is hard to give any advice on that, though.

cachesize was setted to 10000 for this test (it's 10 times bigger than the number of entries in the bdb database)

idlecache was not configured, I redid all test with a value of 10000
(is it necesary reconstruct the bdb database? I did a simple restart)
and the times were very similar.

No, no need to reconstruct the BDB database. Settings in slapd.conf are picked up after a restart.

As a curiosity, servers matched by the first rules are about 5 or 6 times faster to response than servers matched by last rules. I thought that the ACL evaluation time will be uniform because the whole set of rules would be evaluated. this makes sense to someone?

This give me an extra advantage because I can sort the most important
servers first to grant a fast response to critical apps.

ACL evaluation results are stored in the idl cache, so the more a given rule is exercised, the quicker the result sets to that rule should be, if you have a good idl cache setting.

The one other thing I noticed about your configuration is that you had a 9.5MB BDB cache. This may or may not really be sufficient. You have a small number of entries, but you also have a large number of attributes per entry, and if you have extensive indexing, that would also be a factor. I'd be curious if you'd get a performance increase with a larger BDB cache size (say 100MB, where you would have set_cachesize 0 104857600 0) and see if that improved your results.


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