VMware ESXi guest performance problems

Jeff7181

Lifer
Aug 21, 2002
18,368
11
81
I have a VMware ESXi 4.1.0 host running on a Celeron E3300 with 4 GB of RAM and misc hard drives. I know the Celeron is no speed demon, but can't imagine it's not fast enough for what I'm doing with it.

Basically I have a single VM running. It's running Server 2k8 R2 x64 and I've allocated 3.5 GB of RAM to it and 2 vCPU's. The guest disk is on an 80 GB Raptor (WD800ADFS). Then I also have a 1 TB WD Green drive in there for bulk storage.

Under light loads, it runs fine. But, for example, if I copy a large file to or from the server it transfers at about 40 MB/sec for 3-5 seconds, then falls to about 2 MB/sec and the VM becomes almost totally unresponsive.

The guest reports it's using less than 1 GB of RAM, less than 20% CPU, and the highest disk latency I see is 5 ms.

I'm at the point where I'm just going to do a full backup of the server and convert it to a physical server again and ditch VMware. First, I thought I'd see if anyone could make some recommendations to fix the performance issues I'm having. (FYI, it took 15 minutes to open the Windows server backup application on the guest while copying a 30 GB file from it to my desktop PC.
 

Jeff7181

Lifer
Aug 21, 2002
18,368
11
81
I was just thinking... have I allocated too much memory to the guest? 3.5 of 4 GB? I would think 500 MB is enough for the VMware hypervisor, but maybe not?
 

Jeff7181

Lifer
Aug 21, 2002
18,368
11
81
Think I answered my own question. I dropped the VM down to 2 GB of RAM and it's working much better now.
 

theevilsharpie

Platinum Member
Nov 2, 2009
2,322
14
81
ESXi will generally take about 500-750MB of RAM for itself. You should be able to give your VM up to 3.2GB of RAM without any problems.