Hi all,
It seems to be a common problem, you have a virtual Windows 2003 server running Active Directory on a ESX server and suddenly the performance crawls to almost death.
We'll I'm having this problem now too at my company. After checking some stuff out we've found out that it's beeing caused by the System process owned by SYSTEM. Process Explorer tells us that the Hardware Interrupts are using almost 60% of our CPU usage causing the domain controller to slow down. Which then causes our whole Citrix farm to slow down (cause it's using shares etc on the domain controller).
What have we done?
- We've updated the VMware tools to the latest version supported by our ESX servers
- Killed the virusscanner on that server
- Checked if we're using the LSI Logic SCSI Controller, which we do
- Have searches the 'whole' internet and the VMware forum
All with no result 
After a reboot yesterday all seemed normal again but this morning about 07.30 it all started again (see attached screenshot).
Our ESX servers are running WMware ESX Server, 3.0.2, 61618.
Does anyone have an idea about what might be going on here?
Cheers!