Re: restricting slapd memory consumption

[Quanah Gibson-Mount <quanah@zimbra.com>]

--On April 14, 2008 5:04:07 PM +0200 Ralf Narozny <rnarozny@web.de> wrote:

> Quanah Gibson-Mount schrieb:

> > What version of BDB are you using?  Have you patched it with all the
> > relevant patches?
>
> We are using BDB 4.4.20. With as far as I know no patches. Any
> recommended version or neccessary patches?

I guess you didn't take a look at the Oracle download site for BDB.  It 
clearly lists that there are 4 patches available for BDB 4.4.20.

<http://www.oracle.com/technology/software/products/berkeley-db/db/index.html>

4.4.20
 	Requires log file format upgrade. change log - patches (4)

> > What's the contents of your DB_CONFIG file?  What's the size du -c -h
> > *.bdb in your database directory? What is your idlcachesize setting?
> > How many file descriptors do you allocate to slapd?
>
> DB_CONFIG:
> set_flags DB_LOG_AUTOREMOVE
> set_cachesize 4 0 2
> set_lg_max 524288000
> set_lg_regionmax 512000
> set_lg_bsize 268435456


In past tests I did, I found that partitioning BDB into multiple segments 
had a negative impact on performance.  I don't advise doing so unless it is 
absolutely necessary.

Also, as Howard noted, your dn cache is going to grow until it matches the 
full size of the DB.  The only way you can resolve that is to upgrade to 
OpenLDAP 2.4.

I think the long term solutions to your memory issues will be to upgrade to 
2.4 (I'm working on getting 2.4.9 release ready this week, but no promises).

--Quanah


--

Quanah Gibson-Mount
Principal Software Engineer
Zimbra, Inc
--------------------
Zimbra ::  the leader in open source messaging and collaboration