Citrix iForum pre-conference announcements

Will someone (other than Citrix and VMware) do a performance evaluation comparison of running Citrix PS on XEN VS running Citrix PS on VMware ESX?
Whoever comes out on top and allows us to use Citrix Presentation Server on a Virtual Machine without major perfomance hits will really have something.
Thanks for keeping us informed while at iForum Brian.

Performance should certainly not be your only criteria when evaluating enterprise class virtualization solutions... eom

Why virtualize Presentation Servers? Apart from performance considerations there is also the "cost problem": I suppose you only get half the users on the same physical box. And you need ESX (or XenSource) licenses which are not known to be cheap.

Here are a few reasons.
You virtualize Presentation Server for the same reason you virtualize other servers.
Fault Tolerance is great reason.
It is so easy to bring up a VM or have a VM pre-created for DR.
You can transfer a running VM another ESX box with zero down time which is critical in many scenarios.
It is easier to simply bring up another server as needed then to put in a requisition to buy another blade or another server.
I can always have VMs ready for fault tolerance even if I am not using VMs in production. If my production servers go down - I can bring up my backup VMs in a pinch - I may have less performance then I had while running production servers on a non-virtual server but at least I can still run my company - slower but still running.
I think MS clustering is becoming legacy due to the preferred failover capabilities of ESX.
Can you do all this with XEN?

Citrix PS on XEN VS or Citrix PS on VMware ESX??
Virtualize PS for the same reason as you virtualize other servers??
I can't help thinking you're missing the point a little. You're thinking of standard CPS, and simply running that on a VM. That's virtualizing a virtualization technology - and performance will be an issue. Sure performance has improved and some people will do it, but CPS is one way of delivering desktops and apps, and VMs are another - they're both virtualisation technologies but with VMs we're looking at using say, Vista workstations running, maybe accessed via ICA or whatever, not taking what you have now (CPS) and simply running that on VMs. Or have I got this wrong myself?

Using the Phrase "Virtualizing a Virtualization technology" while catchy is a dangerous misconception. Remember that Presentation Server is about Virtualizing the Presentation of the application away from the client machine while Xen or VMware virtualize hardware. This is quite different than stacking two virtualization technologies that address the same isse together, like running Xen on VMware.

Remember that there are virtualization technologies at almost every level of the IT stack today and there is no inherent performance disadvantage (besides any emulation overhead) to running a Vitrual Desktop using a Provioning Server vDisk , running virtualized applications that are streamed or delivered by Presentation Server virtualization running on a Virtual Server backed by Virtualized SAN storage. Each of these virtualization technologies adds a level of flexibility that enables more agility in the face of change.

While not specifically related to CPS, Ron Oglesby did a performance comparison of Xen and ESX (for VDI sessions) at BriForum Europe. Performance wise Xen was pretty close to ESX for all but the highest scale factor, however the IOMeter results were stacked greatly in ESX's favor. YMMV. Shawn

I am installing a Vmware Farm w\ Citrix Servers virtualized. Why? Well most importantly, the customer failed to fully plan out the install. We have run into issues, regarding POWER!!!... The Physical servers are 1u boxes, with max of 20 users. (win2k3 limitations, as 20 users will hit 3.5gb of ram). Win 64 was not a option. With Vmware, we are able to get 4x ctx servers per ESX server= 4:1 ratio, 4u versus 2u. Which doesnt seem like much. BUT consilidating 32 Citrix servers down to 8 is HUGE saving of power. Not to mention that th esx servers are also hosting , load balanced web interface servers, load balanced Citrix CSG servers, edgesight, 5 one off servers for special apps.. So yah, virtulization of citrix servers is indeed a tech that will work. ALSO this is a 640 user citrix farm. no issues at all.
and these are heavy citrix users. NOW on other custoemr, we have overf 1000 users on 3 ESX servers (published apps, versus published desktops) and performance still is there.

Depends on how you install it, and the conifguration. The customer is really happy about the fact of the ability to deploy new citrix servers in 10min, versus the 8hr, previously.

Rippleyaliens