Shibd under load

[Wessel, Keith]

Hi, all,

We're trying to do some performance testing using a very basic SP setup and are running into problems with load caused by shibd.

We've got Apache protecting a static web page with Shib. The system has 4 CPUs and 8 GB of RAM. We're hitting the server with 4 logins a second and, for the first few minutes, we're fine. After that, things start to slide. Running Apache client processes climbs to over 600, load skyrockets. We watched what was using the CPU, and it seems to be shibd.

I've never had a case where I've had shibd be a resource hog, but I know this is extreme. Is there something I can tweak in shibd that might help? Number of concurrent connections or the like? Right now, our Shibd configuration is fairly close to the defaults.

Thanks,
Keith