I'm in the process of attempting to benchmark a multithreaded application on my new HP Proliant Server which has an 2x Opteron 6272 and 64gb of ram.
When I run the application on a desktop machine (a range of i7s and a Xeon X5675 processors) the application will cause all cores to hit a near 100% utilization.
When I run the application on my server, no matter how many threads I run, the total cpu utilization of the application hovers around 20-25%. That is if I'm running with 32 threads, all 32 cores will hang at around 20%, if I run 16 threads they'll hang around 40%, and so on.
- At first I suspected this had to do with the operating system, so I installed Windows 7 on the server so that the desktops and the server had the same OS.
- Then I suspected it was the hardware, I changed the power management in the bios to High Performance. Even though this did increase the benchmark time, the same 20% utilization problem persists.
- I can get all 32 cores at 100% using the y-cruncher benchmark. My custom benchmark is written in .NET, could this possibly have anything to do with it?
I'm perplexed by this problem. Anyone have an idea of what could cause this?