Re: (ITS#5860) slapd memeory leak under openldap 2.4

[quanah@zimbra.com]

--On Tuesday, January 20, 2009 12:07 AM +0000 rlvcosta@yahoo.com wrote:

> Pierangelo,
>
> Executing some test I'm not sure anymore if this is really a memory
> leakage or if some cache issue.
>
> I decided to install CentOS5.2 where I could have OpenLdap 2.3.27
> compiled by the distribution and then execute more tests to check if some
> library in RHEL4 would be causing some problem.
>
> I then use a similar slapd.conf as in my original e-mail just without
> explicitly define an size for cache and idlcache there. My DB_CONFIG file
> has a cache defined as 50MB what is respected.
>
> Looking at some other ITS I found the ITS#3938 what I believe is very
> similar to my problem.
>
> I still have a DB with 3882998 entrances and where the DB files at disk
> is around 15GB. My machine has 12GB of memory where for sure all the DB
> cannot be cached into memory.
>
> In any case what is happening is that every time a transaction is done
> with OpenLdap, even a distribution formal compilation, the cache
> continues to grow until consumes all memory. If the DB is bigger than
> machine memory then soon or later a memory out of range will happen.
>
> The cache is never release by OpenLdap and then if a sequential search is
> done and since DB is bigger than memory we can speed up the problem.

I would suggest you use OpenLDAP 2.4, and set the slapd.conf cachesize, 
idlcachesize, and dncachesize.  I would also review your settings for 
DB_CONFIG, and use a newer BDB version with OpenLDAP 2.4 (i.e., BDB 4.7 
with all 3 patches).  See if that helps resolve the issue you face.  In 
OpenLDAP 2.3, there is no way to control the dncachesize.

--Quanah


--

Quanah Gibson-Mount
Principal Software Engineer
Zimbra, Inc
--------------------
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