RE: slapd hangs at 100% cpu in sched_yield (ITS#2030)

[hyc@symas.com]

> -----Original Message-----
> From: owner-openldap-bugs@OpenLDAP.org
> [mailto:owner-openldap-bugs@OpenLDAP.org]On Behalf Of
> steven.wilton@team.eftel.com

> If we increase the number of lockers, we will just
> delay the problem, as the ldap server becomes busier, and starts
> using even more lockers, we will hit the limit again.

No, this is not an unbounded problem. The maximum number of locks needed is
tied to the maximum number of slapd threads. It will also depend on the
number of attribute indices you have configured. Each index is stored in its
own database, and some number of locks are needed to navigate those databases
as well. You can use db_stat to help arrive at the ideal number of locks for
your configuration. Eventually you will reach a high-water mark and no more
locks will be needed.

See the BDB "Configuring locking: sizing the system" doc for more guidelines.
http://www.sleepycat.com/docs/ref/lock/max.html

  -- Howard Chu
  Chief Architect, Symas Corp.       Director, Highland Sun
  http://www.symas.com               http://highlandsun.com/hyc
  Symas: Premier OpenSource Development and Support