ESX server performance

[seleblan]

Hi all, first post on the VM community board.

I've been using Workstation for about 2 years and I'm beginning to look at ESX server.

One thing I'd like to clarified is the performance issue.

Here's a case I got here :

We have 3 Dell PowerEdge 2900 III with the exact same hardware configuration :

• 1 Quad Core Intel® Xeon® E5450, 2x6MB Cache, 3.0GHz, 1333MHz FSB

• 4GB 667MHz (4x1GB), Single Ranked DIMMs

• Windows 2003 Enterprise Server

One server for application

One server for DB

One server for "other" purposes

We need to replicate the same setup 3 times.

So instead of purchasing new hardware, would it be realistic to install ESX server on each server and create 3 VMs (with the same "hardware" spec as their original conterpart) per server and still get a reasonable performance rate?

Like I said I'm not currently using ESX and I wasn't able to find a "clear" answer to my interrogation...

If you need more info, please ask me... or feel free to "redirect" me to any specific post / thread / doc.

Regards

Sebastien

[DSTAVERT]

It would really depend on the current load. If they are like most servers ie underutilized, you should expect to get reasonably similar performance in a virtualized environment. More RAM in the hosts would be beneficial as would disk caching.

[seleblan]

Well... it was my understanding of the different thing I already read... I wanted to be sure by actually asking to real user.

Thanks for your input...

[DSTAVERT]

Only you will know the existing load on your server. It isn't unusual to have a 10 to one or more ratio of virtual machines to hosts. I have some servers with 15 guests? Do some searching through the forums to see what others have done.

[pavelbernardi]

If you are buying some licenses most resellers will install and run Capacity Planner for you and help you decide if your hardware is ok.

[seleblan]

Thanks guys for your answers...

We are about to proceed with ESX server... can't wait to play with this "Graal".

Regards

Sebastien

[J1mbo · Accepted solution]

As said above, I would look to increase the physical RAM in each to at least 8GB. RAM for those boxes looks inexpensive - £160 from Crucial for 8GB, a little more from Dell no doubt.

Also the RAID controller within each server absolutely needs to have the battery backed cache on it, so that might need to be added as well.

Please award points to any useful answer.