Cluster Help Needed

Need more info:

1. Are you using Jrun Clustering, or other types?

A: Yes, I'm using JRun and building the instances and cluster through the CF Admin interface.

2. What is your memory allocation for the instances?

A: I currently have 2 instances with 3.5GB allocated per instance.

3. what is your total RAM size?

A: The server has 16GB of RAM running Windows 2008 and IIS7.5 on a dual quad core box.

4. CF version?

A: CF9

Can you post the entry on your server.logs which states the "OutOfMemory" issue?

A: I'll see if I can find the OutOfMemory log, but I'm running FusionReactor to monitor the instances and can watch it run out. I originally had 3 instances with 2048MB of memory each, but that was getting maxed out, so I reduced it to 2 instances and increased their memory to the 3.5GB. I'm now in the 70-75% memory threshold and that's fine and everything is holding. When I had the 3 instances and 1 of those instances maxed out it's memory in FR, than the other 2 instances would stop handling requests too. When this happens, the box still has plenty of memory to spare, so I'm not starving the server.

I was wondering if their was some lower level relationship in a cluster, like the IIS connector that would be affected by one of the instances running out of memory or threads? I can stop 1 of the instances and the other instance will continue to run and handle requests fine. It just seems like a memory issue or perhaps the memory issue creates a thread backup and that's causing an issue on the other instance. I'd think that one instance could crash and not crash the other and that's my goal, even if the crash was a memory or thread issue.

I can re-create this if I turn on server monitoring and enable memory tracking for just one of the instances. Eventually the memory gets all used up and both instances stop responding.

-Thanks!