Re: openldap getting very slow

["Sean O'Malley" <omalleys@msu.edu>]

On Mon, 6 Apr 2009, Thomas van Oudenhove wrote:

> hello,
>
> I have some problems with my ldap server. it worked perfectly until
> monday, march 30 : on every night, I used to extract all entries from
> the server, making a diff with some ldif file(s) and ldapmodify with the
> "diff ldif file".
>
> there was about 15,000 to 40,000 entries modified each night, and
> ldapmodify was running about 20 to 40 minutes (~1,000 entries per minute).
>
> on last monday, the extraction of ldap had some trouble, the extraction
> request never ended, and that made the server inaccessible; we had to
> restart it. since march 30, the update process (ldapmodify) is
> incredibly slow, it takes about several hours (~60 entries per minute),
> but the extraction request is "normal" again (about 2 seconds).
>
> we tried to restart from scratch (delete db, re-install openldap (and
> update) and start the process again, it is still slower than before
> (~400 entries per minute). we cannot figure out why it became so slow,
> so we are interested in any advice... we had openldap 2.3.27-8.el5_2.4
> installed and tried with the update: openldap 2.3.43-3.el5 (both CentOS
> packages).
>
> log of the failed request:
> Mar 30 01:10:01 ldap slapd[27383]: conn=1772 fd=16 ACCEPT from
> IP=xxx.xxx.xxx.xxx:38263 (IP=0.0.0.0:389)
> Mar 30 01:10:01 ldap slapd[27383]: conn=1772 op=0 BIND
> dn="cn=Manager,dc=fr" method=128
> Mar 30 01:10:01 ldap slapd[27383]: conn=1772 op=0 BIND
> dn="cn=Manager,dc=fr" mech=SIMPLE ssf=0
> Mar 30 01:10:01 ldap slapd[27383]: conn=1772 op=0 RESULT tag=97 err=0 text=
> Mar 30 01:10:01 ldap slapd[27383]: conn=1772 op=1 SRCH base="dc=fr"
> scope=2 deref=0 filter="(objectClass=*)"
> [and no more traces until openldap restart about noon]
>
> log of a "normal" request:
> Mar 16 01:10:01 ldap slapd[23294]: conn=11 fd=15 ACCEPT from
> IP=xxx.xxx.xxx.xxx:53535 (IP=0.0.0.0:389)
> Mar 16 01:10:01 ldap slapd[23294]: conn=11 op=0 BIND
> dn="cn=Manager,dc=fr" method=128
> Mar 16 01:10:01 ldap slapd[23294]: conn=11 op=0 BIND
> dn="cn=Manager,dc=fr" mech=SIMPLE ssf=0
> Mar 16 01:10:01 ldap slapd[23294]: conn=11 op=0 RESULT tag=97 err=0 text=
> Mar 16 01:10:01 ldap slapd[23294]: conn=11 op=1 SRCH base="dc=fr"
> scope=2 deref=0 filter="(objectClass=*)"
> Mar 16 01:10:03 ldap slapd[23294]: conn=11 op=1 SEARCH RESULT tag=101
> err=0 nentries=39741 text=
> Mar 16 01:10:03 ldap slapd[23294]: conn=11 op=2 UNBIND
> Mar 16 01:10:03 ldap slapd[23294]: conn=11 fd=15 closed
>
> thanks for any help,
> regards,
>
>

Did you try to reindex it? I have had similar issues with MUCH earlier
versions after 4 months or so having them flake out.

I assume you did, but you also need to have defined a checkpoint defined
in your slapd.conf which I do not believe is default or else it gets
messy.