[Building Sakai] Performance problem

[Peter Crowther]

2009/9/30 Joshua Swink <jswink at ucmerced.edu>
>
> We have about a maximum of 600 concurrent users and our performance is
> pretty poor. The application servers aren't working very hard so I
> suspect the database server. It's running Oracle 10 on a Sun V880 with
> 8 GB RAM and 8 750MHz CPUs. We also store the resources in the
> database. The database is about 100 GB in size right now.

I'd check what resources are being used on the database server.
"vmstat 10" on the Sun console will give you a set of reports at
10-second intervals on a really gross level about CPU and I/O usage -
there are more detailed tools, but this can sometimes tell you in
under a minute where the bottleneck is.  In particular, knowing
whether your database server is CPU-bound, disk-bound, network-bound
or none of these would be very interesting.

"None of these" is the really unpleasant one; the others can generally
be solved by throwing hardware at the problem, whereas a system that's
providing poor throughput and hasn't hit any hardware limits is
generally limited by concurrency issues in the application itself.
These take effort to solve, rather than merely taking money!

- Peter