slapd thread hangs on modify operations (ITS#1836)

[norbert.klasen@daasi.de]

Full_Name: Norbert Klasen
Version: head
OS: SuSE Linux 7.3
URL: 
Submission from: (NULL) (172.185.61.154)


Hi,
I have loaded a bdb backend with about 55.000 entries with ldapmodify without
problems. Now I want to replace two attributes on a subset (4000) of these
entries. However, slapd stops processing after about 460 operations, e.g.:

May 24 15:18:49 clara slapd21[26709]: bdb_open: Sleepycat Software: Berkeley DB
4.0.14: (November 18, 2001) 
May 24 15:18:49 clara slapd21[26709]: bdb_db_init: Initializing BDB database 
May 24 15:18:49 clara slapd21[26709]: bdb_db_init: Initializing BDB database 
May 24 15:18:50 clara slapd21[26710]: slapd starting 
May 24 15:19:50 clara slapd21[26712]: daemon: conn=0 fd=16 connection from
IP=134.2.217.66:48443 (IP=:: 389)
May 24 15:19:50 clara slapd21[26775]: conn=0 op=0 BIND dn="cn=admin,c=de"
method=128 
May 24 15:19:50 clara slapd21[26775]: conn=0 op=0 RESULT tag=97 err=0 text= 
[...]
May 24 15:19:51 clara slapd21[26775]: conn=0 op=478 RESULT tag=103 err=0 text= 
May 24 15:19:51 clara slapd21[26776]: conn=0 op=479 MOD dn="ou=Zentrum für
Lateinamerika-Studien,ou=Zentrum für Internationales Management,o=WHU
Wissenschaftliche Hochschule für Unternehmensführung - Otto Beisheim
Hochschule,c=DE" 


doing an strace on this process continually shows:
sched_yield()                           = 0
sched_yield()                           = 0
[...]

while the ldapmodify is blocked:
select(1024, [5], [], NULL, NULL

An attempt to shutdown slapd gracefully gives me:
May 24 15:26:28 clara slapd21[26712]: slapd shutdown: waiting for 1 threads to
terminate

But even after 15min I see no progress and the thread continues to run at 100%
CPU utilization.