In case you’re missing the ICA Session performance counters in perfmon, run that command for XenApp/XenDesktop 7.x:
regsvr32 C:\Program files (x86)\Citrix\System32\icaperf.dll
Change the path of the dll according to your install folder, the one above is default. This will register the dll that brings back the counters:
I’m not sure why they suddenly disappeared on my servers, but that might be a side-effect from a Citrix Hotfix.
The performance counters are very useful when troubleshooting issues, especially on WAN connections. You can monitor the network latency and bandwidth used from your XenApp server to all the end clients of the users connected to the server. Also HDX Monitor gets the data from these counters.
Update 08.09.2014: Citrix provided a hotfix that brings the performance counters back: http://support.citrix.com/article/CTX141330