Running Citrix Presentation Server Performance Issues

[RSG]

We are thinking of virtualizing our Citrix physicals to a VMware environment. I have heard from colleagues that there are issues to be aware of when virtualizing Citrix and performance degradation. Anyone know about this area and what to look out for?

[NTurnbull]

Hi, there is a Citrix scalability & performance VMware doc - although it is from 2006.. Also found another article based on experience here . I'm sure other people will be able to give you some more in depth 'learnt from experience nuggets' but hey, something to get you going

Thanks,

Neil

[dtracey]

Hi,

A couple of links and an attached document (from VMworld) regarding Best Practices for deploying Citrix Presentation Server within VMware to get your teeth into!

http://virtrix.blogspot.com/2007/03/vmware-best-practices-for-deploying.html

http://www.brianmadden.com/blogs/gabeknuth/archive/2007/08/27/a-short-guide-to-virtualizing-presentation-and-terminal-servers-on-vmware-esx-3.aspx

Hope it helps,

Dan

[CaptOchs]

The short answer is "it depends on the applications you run." Some DOS & 16-bit applications don't run well if they are cpu interrupt heavy. Create a test VM first and validate all of your applications before a migration. If you're looking for a number, figure you have about 75% of capacity with VMs; e.g if you have 6 servers plan on 8 VM servers. For best performance rebuild your Citrix servers, don't P2V them. My VM's have a single CPU with 2GB RAM and 20GB of space and they run pretty well. VMWare works great for Citrix for deployment. You can create templates and deploy servers quickly. I can get a new server up and ready for users in about an hour!

[mikejroberts]

Gets old hearing the "it depends" answer. I have both physical and virtual PS 4.5 servers (x64 & x86), running a variety of applications, and the users can tell a difference. I would say it is most noticeable during logon. Launching one of my applications (RetaiLease in this case) takes about 2 or 3 seconds longer on a VM and the screens take longer to refresh. My VMs are equivalent to my physical servers in RAM and CPU and the hosts are not oversubscribed. I would guess that we get about 80 - 85% of physical performance, but I have no true way to measure. Once logged in, most users don't notice a difference.

[CaptOchs]

Well here it is again... IT DEPENDS...

:smileywink:

We could get into questions about your setup, but a 2-3 second increase in logon is hardly worth it. I publish Office 2003 to users and I just had to build more VM's to get performance acceptable. That goes back to the 75% figure I mentioned to reduce the amount of users per VM.