slapd gets in endless loop with sched_yield

Message-Id: <email address hidden>
Date: Mon, 04 Apr 2005 00:11:36 +0200
From: Hans-Joachim Baader <email address hidden>
To: Debian Bug Tracking System <email address hidden>
Subject: slapd gets in endless loop with sched_yield

Package: slapd
Version: 2.1.30-3
Severity: important

Since a few hours slapd hangs during start. strace shows that it
permanently does sched_yield and nothing else. It can only be killed
with kill -9 or kill -2.

Adding a -d 32767 option for slapd apparently shows nothing. The PID
file isn't crated, perhaps it hangs before it comes to that point. I
cannot tell if the BDB database is corrupt but none of its files has
a recent timestamp.

The configuration hasn't changed in the last 14 months and the demon
was running during the 26 days of system uptime. It's a SMP system.

I have updated some packages slapd depends on (like libgnutls11) but
it didn't help.

slapd was running with the following arguments:
/usr/sbin/slapd -h ldap:/// ldaps:/// -g ldap -u ldap -4

Here's a stack trace (I wonder if that can be correct, I guess it's
bdb_db_open rather than bdb_bt_compare:

(gdb) bt
#0 0x4040e497 in sched_yield () from /lib/libc.so.6
#1 0x4002cb89 in ldap_pvt_thread_yield () from /usr/lib/libldap_r.so.2
#2 0x4011bf13 in __os_yield_4002 () from /usr/lib/libdb-4.2.so
#3 0x4007c730 in __db_tas_mutex_lock_4002 () from /usr/lib/libdb-4.2.so
#4 0x400fd8c2 in __db_e_attach_4002 () from /usr/lib/libdb-4.2.so
#5 0x400f9bbe in __dbenv_open_4002 () from /usr/lib/libdb-4.2.so
#6 0x405ce8b0 in bdb_bt_compare () from /usr/lib/ldap/back_bdb.so
#7 0x080659b8 in backend_startup ()
#8 0x08051670 in main ()

-- System Information:
Debian Release: 3.1
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)
Kernel: Linux 2.4.28
Locale: LANG=de_DE, LC_CTYPE=de_DE (charmap=ISO-8859-1)

Versions of packages slapd depends on:
ii coreutils [fileutils] 5.2.1-2 The GNU core utilities
ii debconf 1.4.30.10 Debian configuration management sy
ii fileutils 5.2.1-2 The GNU file management utilities
ii libc6 2.3.2.ds1-16 GNU C Library: Shared libraries an
ii libdb4.2 4.2.52-18 Berkeley v4.2 Database Libraries [
ii libgcrypt11 1.2.0-4 LGPL Crypto library - runtime libr
ii libgnutls11 1.0.16-4 GNU TLS library - runtime library
ii libgpg-error0 1.0-1 library for common error values an
ii libiodbc2 3.52.1-2 iODBC Driver Manager
ii libldap2 2.1.30-3 OpenLDAP libraries
ii libltdl3 1.5.6-2 A system independent dlopen wrappe
ii libsasl2 2.1.19-1.1 Authentication abstraction library
ii libslp1 1.0.11-4 OpenSLP libraries
ii libwrap0 7.6.dbs-5 Wietse Venema's TCP wrappers libra
ii perl [libmime-base64-perl] 5.8.4-8 Larry Wall's Practical Extraction
ii psmisc 21.5-1 Utilities that use the proc filesy
ii zlib1g 1:1.2.2-3 compression library - r...

Message-ID: <email address hidden>
Date: Mon, 4 Apr 2005 08:27:07 +0200
From: Torsten Landschoff <email address hidden>
To: Hans-Joachim Baader <email address hidden>, <email address hidden>
Subject: Re: Bug#302992: slapd gets in endless loop with sched_yield

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Hi Hans-Joachim,=20

On Mon, Apr 04, 2005 at 12:11:36AM +0200, Hans-Joachim Baader wrote:
> Since a few hours slapd hangs during start. strace shows that it
> permanently does sched_yield and nothing else. It can only be killed
> with kill -9 or kill -2.

slapd 2.1.x is a dead end as far as Debian is concerned because of
problems like this one. There are a number of bug reports about slapd
locking up, using 100% CPU, etc. - see http://bugs.debian.org/255276
for example.=20

Most of the time running db4.2_recover in the database directory seems
to help but most of the time the problem will reappear.=20

I suggest upgrading to 2.2.23-1 from unstable ASAP. That's the upstream
version that will ship with sarge.

Greetings

 Torsten

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Message-Id: <email address hidden>
Date: Mon, 4 Apr 2005 08:27:26 +0200 (CEST)
From: <email address hidden> (Torsten Landschoff)
To: <email address hidden>
Subject: severity of 302992 is normal

severity 302992 normal

Message-Id: <email address hidden>
Date: Mon, 4 Apr 2005 08:27:47 +0200 (CEST)
From: <email address hidden> (Torsten Landschoff)
To: <email address hidden>
Subject: merging 302992 255276

merge 302992 255276

Message-Id: <email address hidden>
Date: Mon, 4 Apr 2005 18:32:29 +0200 (CEST)
From: <email address hidden> (Torsten Landschoff)
To: <email address hidden>
Subject: merging 303057 302992

merge 303057 302992

Message-Id: <email address hidden>
Date: Mon, 11 Apr 2005 23:19:19 +0200 (CEST)
From: <email address hidden> (Torsten Landschoff)
To: <email address hidden>
Subject: severity of 303057 is serious

severity 303057 serious

Marking as duplicate based on debbugs merge (255276,302992)

This bug has been marked as a duplicate of bug 15270.