RE: How to improve performance with MDB backend?

[Chris Card <ctcard@hotmail.com>]

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> Date: Thu, 18 Apr 2013 08:16:03 -0700
> From: quanah@zimbra.com
> To: ctcard@hotmail.com; openldap-technical@openldap.org
> Subject: RE: How to improve performance with MDB backend?
>
> --On Thursday, April 18, 2013 2:27 PM +0000 Chris Card <ctcard@hotmail.com>
> wrote:
>
> > I am also interested in this thread. I've been doing some comparison
> > tests between MDB and BDB using openldap 2.4.35, and find that the BDB
> > backend is consistently much faster for writes. For example, modifying
> > 10000 DNs and changing one attribute using ldapmodify takes about 80
> > seconds with an MDB backend and about 18 seconds with a BDB backend. Is
> > there any chance that MDB write performance will catch-up (or even
> > overtake) BDB write performance?
>
> Did you make the changes to the DB flags for MDB that I noted the other
> day? For me, MDB writes are a minimum of 65 times faster than writes with
> BDB/HDB, even when BDB/HDB use an SHM key.
Yes. I have these values in my mdb configuration:
olcDbEnvFlags: writemap
olcDbEnvFlags: nometasync

I think these setting may have helped to speed up slapadd, but not ldapmodify.


Chris