VM Network Performance

[dontinou]

Hi,

This is probably a stupid question, but I was wondering what normal transfer rates are to/between VMs on the same ESX host running Win2K3 R2. The setup is:

ESX 3.5, local SAS 15K storage, VMDK storage (not raw), VMware Tools 3.5-110268 on all VMs, Accelerated AMD PCNet Adapter driver, host is 2x X5460 cpus (8 cores total)

Running this simple program as a test:

Physical to Virtual - 85Mbps Write and 165Mbps Read

Virtual to Virtual - 200Mbps write and 320Mbps Read

If I go from a Physical to Physical test on a gigabit switch, I get ~500Mbps write and ~500Mbps read.. big difference.

Any comments or explanations, or is this normal? Do you mind running a test on yours and telling me what results you get? Also list your setup pls.

Thanks a million!

[AntonVZhbankov]

You habe disk-network-network-disk operation. So pay attention to disk-network operations, especially on the same host. I met many complaints about ESX speed with disks, but not with network.

I got 890 Mbps network transfer rate on ESX4 RC synchronizing mirrors in Xtravirt Virtual SAN (drbd) on two SUN x4150 servers witj high speed local storage.

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VMware vExpert '2009

http://blog.vadmin.ru

[dontinou]

wow that is a fast number.

But I'm simply running 1 ESX box on local SAS storage. What more can I do to make this faster? What things can I check?

[AntonVZhbankov]

I don't know what this program measures and how. I know that real numbers I got myself are about 890 Mbit of real load on 1 Gbit card, so all synthetic tests mean nothing.

---

VMware vExpert '2009

http://blog.vadmin.ru

[dontinou]

ok so given that, how do I troubleshoot my slow speeds given my setup? What would you do?

[ROMCH]

You tool measures the performance of the NETWORK and the DISK. If you are intressted in the Network perfomance use the following tool:

http://iperf.sourceforge.net/

Click on JPerf 2.0.0 Released then download/browse all packages. Select jperf 2.0.0 release and download jperf-2.0.0.zip. Extract it with folder names to your preferred path. On Windows launch jperf.bat and get GUI....

Start one JPERF as Server and one as Client.

[dontinou]

the link you provided does not work.

Secondly, can someone please answer my question about how I'm supposed to troubleshoot slow disks when I'm running from direct SAS 15K storage? Theres not much I can tweak here.

[ROMCH]

1. Use RAID1 or RAID 10 and as many as possbile SAS 15K DISK. This will speedup you DISK-Array.

2. Check if your SAS Raid-Controller and Firmware complies with the VMARE HCL.
   VMWARE HCL

3. Apply all VMware Updates so you are runnig ESX 3.5 build number 176894.