VMWare ESXi and ZFS performance...

[Rectal Prolapse]

Hi - I read a lot about how people here run VMWare ESXi with OpenSolaris or OpenIndiana. I would like to know how the performance stacks up against a native (non-VM) installation.

How well would this perform with 2 or 3 LSI 1068E cards with 10 drives in RAIDZ2?

Currently I am getting approximately 250 MB/sec copying files from one zpool to another (both RAIDZ2), which isn't too bad for a C2D Q9300 and 3 HBAs. It would be nice to have the ability to run another OS like Windows 7 through ESXi instead of as a Virtualbox instance under OpenIndiana.

 

[_Gea]

1. you will get nearly the same performance if you:

- use your 1068e with passthrough (mainboard with vti-d required)
- have as much RAM like on a real Installation (the more the faster, 4GB+)
- use all cores
- use vmwnet3 netdriver if available with your vmware-tools to have
more than Gigabit-performance between VM's


but: (general problems with ZFS)
a raid-z2 pool is rather slow:

for VM's on a NFS Storage you need IOPs more than max sequential performance
for this scenario Raid-Z2 is bad, create a pool of mirrors instead, at least with a small mirrored pool for your vm's.
Also there are a lot of syncronous writes that needs a fast ZIL (a sort of cache drive for syncronous writes)

i would suggest:
-use a raid-1 or raid-10 for your VM's and the rest as a raid-Zx
-add SSD Read and/or Write Caches or use a SSD only mirrored pool to store VM's.

otherwise your win7 would perform slow
-not only with graphic-performance but also with all disk related things

i have suggested this all-in-one concept more than a year ago and
use it now with all my VM and ZFS-SAN installations

see some more infos of my all-in-one concept at http://hardforum.com/showthread.php?t=1573272 or
http://www.napp-it.org/napp-it/all-in-one/

If you have questions about my concept, please ask in obove thread

Gea

 

[sub.mesa]

I would use an SSD if you need random I/O performance; a 200-disk RAID-Z2 would have the same Random I/O performance as a single disk; the size of type (RAID-Z/ RAID-Z2/ RAID-Z3) is not important; all disks in the RAID-Z will be involved in a single I/O operation; thus the IOps is the same; HDDs are limited by seeks.

But you can use a large RAID-Z and hook up an SSD for L2ARC and SLOG; especially if you use ZFS pool version 19 and got a third generation SSD with supercapacitor (Intel G3, SF2000/2500, Marvell C400). This would accelerate your random I/O considerably, without needing to revert to mirroring; which is faster yes but doesn't come close to the speed of SSDs.

 

[Rectal Prolapse]

Thanks for the replies guys - I'll research some more.

I have 3x1068E cards, but VMware ESXI 4.x only supports 2 cards in passthrough - that can be a problem!