Re: 99.9% CPU usage still, production system

["Kurt D. Zeilenga" <Kurt@OpenLDAP.org>]

At 07:28 AM 2001-10-21, Nick Urbanik wrote:
>Thank you to all the good suggestions to my previous questions.  I have
>added ulimit -n 16000 to /etc/init.d/ldap, and have rebuilt the indexes
>after stopping the system late at night.

Note that slapd won't use more descriptors than FD_SETSIZE.
On some systems, this can be redefined a compile time
(-DFD_SETSIZE=16000), but on others it requires hacking
system headers and, possibly, rebuilding the world.

>However, I still have 99.9% CPU usage occasionally, and often students
>cannot log in and get their home directories.  We are using LDAP as a
>NIS replacement.  I am desperate, and have expended much energy in
>this.  With linux-2.4.10-ac12 the slapd process no longer dies, but the
>system is not available to our students at the start of each laboratory
>session.

You might ask folks on the nssldap@padl.com list for details
on how to improve nss_ldap use of the directory.  From what I
gather, using a caching daemon such as nscd is recommended.

I note that if slapd appears to be in a tight select busy loop,
you might experiment with usleep() within this loop.