[Deploying Sakai] Server slowdown

[Matthew Buckett]

On 27 April 2010 22:31, Grossman,John E <john.grossman at mdanderson.org> wrote:
> One of our Sakai production servers slowed to a near standstill with about
> 90 users logged in and taking final exams. We are running Sakai 2.6.0 on a
> 4-processor 64-bit Windows machine with 8 GB of RAM with 5 GB allocated to
> the JVM. The chain of errors started with those in the attached zip file.
> Eventually no one could log in and it would take 10-15 minutes for a user
> interface action such as a button click to take effect. Processor
> utilization on the server was 0-2% during this episode and there was about
> 200 MB of available memory according to the Memory tool in the admin
> workspace. Would appreciate any suggestions.

I think the errors in your attached file could well be related to this
issue in JIRA:

http://jira.sakaiproject.org/browse/SAK-6553

I don't have any good ideas as to why the server became slow, if there
the CPU load is low and there isn't much disk activity locally I'd
look for exhaustion somewhere:

- Database connection pool.
- Tomcat worker threads.

Do you have the DB on a separate machine?
Do you have more than one tomcat worker node?
Is so what's doing your frontend load balancing?

-- 
  Matthew Buckett
  VLE Developer, LTG, Oxford University Computing Services