Virtualizing SharePoint 2010 FAST Search component

[apatts]

My organization is in the process of rolling out SharePoint 2010 - thus far the WFE, App, and SQL servers are all going to be deployed in the virtual environment but our consultant is holding out on the FAST Search Server module due to I/O performance concerns.  They are referencing a Microsoft study that benchmarked the FAST component on Hyper-V in late 2010 and compared physical and virtual installs (see link).  They found that performance was anywhere between 30-70% poorer running virtual due to I/O - I obviously have a hard believing these same numbers can be applied to a properly configured vSphere/ESXi 4.1 implementation.  I'm sure it will be resource intensive, but that's fine I have plenty of resources in my cluster and will be upgrading to v5.0 in the next 6 months or so, further removing any scaling limitations.  Our storage backend performance (FAS3240) is no concern whatsoever for at least our initial implementation, physical or virtual.

So, does anyone have any experience virtualizing the FAST search component?  What kind of SharePoint environment are you running it on (userbase / object count)?  I've found little information on the interwebs in regards to this other than the Microsoft capacity white paper:

http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=5120

Thanks.

-Adam

[sketchy00]

We will be doing this within the quarter (we are still on SharePoint 2007, but will be upgrading soon), so I don't have an answer for you now, but I will in a bit.

Note that in the document it states: "The major degradation stems from the lower IO performance when running in a virtual machine..."

This seems to be a bit alarming, as in, if properly architected, why would they expect lower IO performance from the VM?  I'm not a Hyper-V guy, nor am I completely familiar with how they set up this test (didn't get that far), but I'm a bit suspicious.  Okay, I'm very suspicious.

Perhaps a question for you.  Take a look at a VM of yours with the most intensive I/O (perhaps a SQL server, etc.), and are you ever stressing any of your disk I/O?  I have have a love/hate relationship with most system requirements documentation.  Here is why:  http://itforme.wordpress.com/2010/01/03/resource-allocation-for-virtual-machines/

[apatts]

You have some good points in your blog post about vendor requirements - I seem to deal with these types of issues on almost a daily basis where physical-server-demanding managers and app admins don't believe me when I tell them their app will probably run fine in our virtual environment with 25% or less of what the vendor recommended specs are (which I'm always vindicated later when it turns out to be true).

In regards to this particular deployment however, it was decided we should go physical for 'political' reasons (consultant / management relationship) - luckily I get to spec out the servers to be the same as all my VM host boxes for when I propose virtualizing it later down the road.  We'll see how it runs once we get a production workload on it; I'll post a follow up in a few months and would also be interested in what kind of performance demands your FAST environment would be requiring once you deploy as well.

[sketchy00]

Thanks for the update to your situation.  I can certainly understand the political factors coming into play.  I will be sure to keep you posted on how things perform for us.