We have a Citrix PS4.0 farm made up of 2 physical and 2 virtual Citrix servers. Any one of them at some point or another will eventually degrade in performance due to hitting 100% CPU usage. I can see the CPU usage spike in the Virtual Infrastructure Client when this happens on either of the VMware servers.
This is not a load issue related to the number of users as it can happen at any time with any number of users.
Users are running shared desktops, not applications. Installed applications in the desktop are standard office application (Word, Excel, Outlook) with limited Internet Explorer access through a Bluecoat Proxy and a couple industry-specific applications.
What tools can be used to troubleshoot and diagnose the source of the problem? Once the server hits 100% CPU, it is impossible to log onto and see what process is consuming all the resources. The only recourse is to hard reset the machine. All servers restart at 4am each morning on a schedule.
NOTE: I already have ThreadMaster installed on all Citrix servers using the default configuration options and logging activities. The logs do not reveal the source of the problem.
EDIT
- Citrix Presentation Server 4.0, Enterprise Edition
- Hotfix PSE400W2K3R03
- Windows 2003 Server Standard Edition Service Pack 1
- Runs Symantec Client Security 10.0.0.359 configured per the recommendations from Citrix for file exclusions, etc.
Best Answer
Windows 2003 SP1 went out of support in April, so your OS does not get any security patches anymore. You need to upgrade to SP2 ASAP.
SP2 also has lots of random bug fixes in it - your issue could go away.
If your OS has that old a patch level, there is a good chance some drivers - specifically print drivers - could be out of date on the box too. As drivers are a big source of system instability in general, I would try checking they are all signed and up to date. Having a dodgy print driver would explain why it affects both virtual and physical boxes, and appears to occur randomly regardless of load.
Oh and FYI Citrix 4 goes EOM (End of Maintenance, no more bug fixes) at the end of this month June 09, and EOL (End of Life, no more security patches or any other patches) at the end of Dec 09. Enjoy your upgrade cycle!