memory leak

[Paul DiSciascio <thenut@gmail.com>]

We are running a cluster of 2 ldap servers using the syncrepl overlay with mirror mode.  After upgrading from SLES 10 SP2 (openldap 2.4.11)  to SLES 11 SP1 (openldap 2.4.20), we have encountered a memory problem.  The slapd process grows unbounded to the point that it uses all of the memory available to the ldap user on the server, currently 2.5GB, in a matter of hours.  The database only contains around 30,000 records, so this amount of memory usage seems unusually high.  No changes to the server configuration were made during the upgrade.

In an attempt to address the issue, we upgraded both instances further to openldap version 2.4.28, but this has not helped.  Below is the slapd.conf (security related pieces have been redacted) that we are using.

~Paul

-------------------BEGIN SLAPD.CONF--------------
# See slapd.conf(5) for details on configuration options.
# This file should NOT be world readable.
#
include         /etc/openldap/schema/core.schema
include         /etc/openldap/schema/cosine.schema
include         /etc/openldap/schema/inetorgperson.schema
include         /etc/openldap/schema/rfc2307bis.schema
include         /etc/openldap/schema/ppolicy.schema

pidfile         /var/run/slapd/slapd.pid
argsfile        /var/run/slapd/slapd.args

# Load dynamic backend modules:
modulepath      /usr/lib/openldap/modules

TLSCipherSuite          HIGH:MEDIUM:-SSLv2
TLSCertificateFile      /etc/openldap/cert.pem
TLSCertificateKeyFile   /etc/openldap/cert.key

<ACLs go Here>

loglevel    none

ServerID 1

#######################################################################
# BDB database definitions
#######################################################################

database        bdb
suffix          "dc=redacted"
checkpoint      1024 5
cachesize       10000
overlay         ppolicy
rootdn          "cn=redacted"
sizelimit       -1
ppolicy_default "cn=redacted"
ppolicy_use_lockout

directory       /var/lib/ldap
# Indices to maintain
index   cn,sn,uid       eq
index   entryUUID       eq
index   entryCSN        eq
index   member          eq
index   objectClass     eq

overlay         syncprov
syncprov-checkpoint 100 10
syncprov-sessionlog 100
limits dn.exact="uid=replica,ou=redacted" time=unlimited size=unlimited

syncrepl rid=501
  provider=ldap://peerhost:389
  type=refreshAndPersist
  retry="5 5 300 +"
  searchbase="dc=redacted"
  attrs="*,+"
  scope=sub
  bindmethod=simple
  binddn="uid=redacted"
  credentials=
  interval=00:01:00:00

mirrormode on

database monitor
-------------------END SLAPD.CONF--------------