Re: Performance Problems

[Christoph Neumann <enigma@apu.edu>]

OK.  How do I set "DB_TXN_NOSYNC".  I can't find a reference to it in the 
Administrators Guide and the Faq-o-matic doesn't specify how to use this 
value.  I did find "dbnosync" in "slapd-bdb" man page.  Is that the same 
thing?

- Christoph


On Mon, 11 Nov 2002, Ian Logan wrote:

> Have you tried changing/setting some of the bdb tunables?
> You might try setting DB_TXN_NOSYNC while you're running slapadd,
> that can make a big difference. You might also want to increase
> the size of your bdb cache, if I remember right they default pretty small.
> Ian
> 
> On Mon, Nov 11, 2002 at 01:01:42PM -0800, Christoph Neumann wrote:
> > We are testing openldap 2.1.8 as a slave in our production enviroment.  We 
> > have experienced serveral problems.  I am wondering if other people are 
> > experiencing the same problems or if they have solved some of these 
> > problems.
> > 
> > Some notes about configuration:
> > * have about 20,000 entries--mostly "people" entries
> > * using BDB backend (db4-4.0.14-14 installed)
> > * indexing several fields:
> >   index   objectClass             pres,eq
> >   index   uid                     pres,eq,sub
> >   index   uidNumber               pres,eq
> >   index   gidNumber               pres,eq
> >   index   mailacceptinggeneralid  eq
> >   index   apuidnumber             eq
> >   index   rid                     eq
> > 
> > 1. slapadd is *very* slow compared to the using slapadd with back-ldbm on
> >    openldap 2.0.25.  slapadd now takes about 45 minutes, whereas it used to
> >    take about 4 minutes.  The only way I have found to fix this, is to
> >    slapadd with all the indexes turned off.  Which leads to my next
> >    point...
> > 2. slapindex is *very* slow.  It takes about 45 minutes to reindex.  It
> >    doesn't matter if slapd is running or not.  It still take forever.
> > 3. My "uidNumber" index is corrupt.  I rebuilt the database from an LDIF
> >    when I upgraded the slave to 2.1.8, so there still must be index
> >    corruption issues.
> > 
> > Anyone else experiencing this?  Anyone have ideas on what might be going
> > on?  I have never had OpenLDAP behave this slowly on me before.
> > 
> > - Christoph
> > 
> > 
> > 
> 
> -- 
> Ian Logan
> Information and Communication Technologies
> New Mexico State University
> Email: ian@nmsu.edu Phone: 505-646-6034 Fax: 505-646-4560
> 
> 
>