VMWare ESX 3i 3.5 Speed vs Physical

(Note - Red is Physical Machine with 8 CPUs, Blue is ESX 3i 3.5 with 4 CPUs)

If you're serious about moving to Virtual Servers, you're going to want to know what type of performance hit you're taking for using this technology.

My rough, fairly unscientific results show that using ESX 3i 3.5;

CPU - About 5-10% less than physical

Memory - Nearly physical speed

Disk - Between 50%-75% of physical speed.

Disk takes the largest hit, so you best make sure to follow all the standard ESX "best practices" - Use SAS drives, put Swap on a seperate controller, etc, etc.

Details follow:

I have a new ASUS DSEB-D16/SAS motherboard that I have been running some tests on. So far the speed has ben quite good for ESX 3i 3.5.



My test platform:

- ASUS DSEB-D16/SAS Motherboard

- Two Xeon 2.0 GHz Quad Cores, 45nm

- 8 Gigs ECC Kingston Ram, 667Mhz

- 2 Segate 250 SATAII Drives, set up as Stripe





I've made some tests with Windows 2008 RC1 in both 64 and 32 bit modes, and with Windows 2003 64 bit mode.



I've always used the latest Window drivers for the board and controller.



I used PassMark 6.1 for my testing - It's not overly in depth, but it gives a good overview for what I'm wanting to do.

There is one major messup that I didn't expect - I can only run 4 virtual CPU's in 3i, not the 8 that I have. The first test was with 8 CPUs, and thusly the CPU speed is roughly 50% less in my 3i run. Passmark does make use of every CPU for the CPU portion of the tests (and it runs single CPU for the Memory and Disk mark tests), so this will affect the CPU portion of the tests only.

I have run the test again with only 2 virtual CPUs in 3i, and the results were roughly 50% less than with 4 CPUs. It stands to reason that wil a full 8 CPUs in 3i we'd be very close to the speed of the physical machine.

All my 3i settings are pretty default. I'm going to switch to SAS drives shortly, but I wanted to see the disk test speeds with the existing SATA 250s I used for Windows 2008.

So far, so good. I'm happy with the 3i speed. I can use 32 meg of RAM with my current setup, and it's less than $100 for a 2 Gig stick of ECC 667. I'll keep the RAM high so it's not swapping to disk, and minimize my performance hit on the drives with beefy SAS drives.

ASUS DSEB LSI 1068 MegaRaid Speed vs Intel Matrix

Okay, spent a few hours making some speed tests between the two built in controllers.

I have stats to back up my words, but I don't feel like dragging out all the tests I did and splicing up the graphics/results. I may get to it later.

In a nutshell, with Windows 2008 RC1 64 Bit on a ASUS DSEB-15/SAS Board with 2 Xeon Quads;

- Intel Matrix controller is ever-so-slightly faster for SATA drives than the LSI Megaraid, but not enough to really worry about.
- ESX 3i 3.5 does see the Intel matrix controller, but doesn't see the RAID sets created on it - Just the individual drives.

It looks like you'll still need the SAS option for this board if you want to run RAID of any kind in ESX 3i 3.5

VMWare ESX 3.5 and 3i on ASUS DSEB-D16/SAS Motherboard with SATA drives

Okay, the board arrived yesterday. So far both VMWare's ESX 3.5 and 3.5i are able to boot, install, and stay stable.

I'm not using the LSI SAS controller as of yet - Just the Intel Matrix controller, with a plain old SATA drive. I haven't created any RAID, so both versions of 3.5 are able to spot the Intel controller and work just fine.

This means that people wanting to save a few bucks could use the Intel 6321 controller only board (no SAS).

Watch out - Make sure you use SATA ports 1-4. Ports 5 and 6 are not spotted by the install scripts.

Welcome

I've been making use of all the great technical information out on the net for over a decade now.

It's an invaluable resource to someone in the IT industry like myself, so I thought it was time to start contributing, to give back to the general net community.

I'll be posting various tidbits of information here that I think others may benifit from.