[Samba] winbind caching problem

[Thomas Vaught]

We are having what appears to a caching problem with winbind going against an
ActiveDirectory server. It seems that each and every request for user or group
information causes a cache update regardless of the time interval between
requests. This causes a very large performance problem since subsequent
requests seem to queue behind the initial request until all of the cache
updates are complete.

According to the documentation, winbind cache updates should only occur if
the items in the cache have expired and the entry on the ActiveDirectory
server has
changed.

What could be causing our winbind cache to behave the way it is behaving?

Are there any good resources for troubleshooting performance problems
such as this?

Is there some way to limit the organizational unit used by samba/winbind
so that the queries are faster?

Below are the versions of software we are using:

samba-3.0.14a-1
krb5-libs-1.2.7-47
krb5-devel-1.2.7-19
krb5-workstation-1.2.7-47
pam-0.75-51

Thanks for any help.

-thom