Romex Software Forum

Hi,
I've been quite close to HW virtualization, terminal solutions (Terminal services, Citrix) or desktop virtualization (VmView, XenDesktop,...) etc. etc.

The common feature of such solutions is that they run on virtual hardware. (ESX VMWare, Hyper V, XenServer etc.)

These In many cases these solutions share many resources. (Storage, CPU, memory, ....)

Consider architecture like this:
1000 virtual Windows desktops running on top of
30 ESX VmWare servers which are connected to
1 enterprise storage
(This is pretty common.)

The risks:
Shared sources can be easily depleted.
On CPU level this is pretty well handled.
On ram level this has been also covered. (Either you have that ram or not.)
With storage the situation is a bit specific. Normally it is considered that disk CAPACITY is a problem. Which is not true because in such scenarios IOPS are the actual problem. (Which is normally not considered.) Moreover there does not exist a any product which would be capable of throttling IOPS!

I believe that FancyCache is the optimal product for implementation of IOPS throttling feature. (It would of course potentially limit the performance of the single machine, but it would ensure that other machines (sharing the same local storage) are still ok and not affected by high IOPS demand of single hungry machine.

At the same time this will be a key selling point for enterprises. Considering also all FC's caching capabilities, it would be a killer app. (I of course understand that such feature is not interesting for people running FC on their PCs or physical servers with dedicated local storage. (=local disks ) )

Interesting thinking Horizon. Given a normal usage pattern for the desktops and enough RAM for FC, users needn't even be aware of any throttling. They would perceive full speed, unless they'd be moving excessive amounts of data.
Great . Romex, please consider Horizon's idea. It might give FC a great advantage over Supercache, eBoostr etc.

Great, few people notice the IOPS.
To some extent FC can reduce the loads of the storage's IOPS, because some IOs are handled by FC and not forwarded to the storage. But currently it can't throtte IOPS and do load balance. We'll follow your suggestion and do a study.
Thank you.

BJameson:
Well, yeah it's just an idea, resp. feature request. (For addressing the problem that many companies have already been facing or will be facing very soon. (Especially if they are considering plan "Desktop As A Serverice" or "migration to Cloud" etc. etc.)

It has been discussed quite intensively by the people who are already in (desktop)virtualization/cloud business. (For example Daniel Feller who is desktop virtualization architect in Citrix: http://virtualfeller.com/tag/iops/ )

I personally have been noticing IOPS on daily basis because I've been running my environment on the shared storage. (Which was designed some time ago and potential IOPS limits (whcih once reached kill every machine running there) were not considered during the design stage...)

Support:
That's true, savings already occur by the fact that caching is in place.
Well, if you'll decide to pursue IOPS throttling I'll be happy to give a hand on POC/research...

Now it's time to hop-on, I believe...

http://community.citrix.com/display/ocb ... ualization