Re: Help: Slow LDAP search with high %iowait
Hi,
Victor <victorfuman(a)yahoo.com> writes:
Hi Dieter,
Many thanks for your response. I increased the cache size by 10 times in both
slapd.conf and DB_CONFIG. The performance got improved, but not impressive.
For example,
Searching by first name only using "scott*" only (for wildcard) for the 1st
time still took 12937 ms to find 881 users (BTW, I was using SpringLDAP Java
client). My other responses are inline.
Ah, java clients. Performance of java clients is really a design
matter. To my experience in most cases java clients are badly designed
and in most cases responsible for performance loss.
Try OpenLDAP tools or a benchmarking tool to get comparable results.
Something like
time ldapsearch <parameters>,
charge, http://loadtesting.sourceforge.net,
slamd, http://www.slamd.com.
I wanted to consider scaling factor. If we use OpenLDAP in production, we will
have over 350million user entries. I probably don't want to put so many
entries in cache unless it is really needed. That is why I used a relatively
small cache in my prorotyping (in the hope it can scale up).
Howard Chu has conducted some large scale tests, search the archive
for his reports.
Did I have a flaw in organizing/grouping the data/entries? Any
further advice
will be greatly appreciated. Thanks.
-Dieter
--
Dieter Klünter | Systemberatung
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