very high memory overhead

[mabene]

Hi,

I'm running a couple of linux (gentoo) systems on vmware ESXi 3.5 (Build 113338); considering information from the vmware resource guide, the memory overhead I see for my machines seems excessive:

All virtual systems share these properties:

• Single CPU

• 32-bit OS

• Single Harddisk (on iscsi storage)

Memory for the virtual systems is different:

MEM	Overhead
512	478,33
256	496,61
512	585,65
768	600,72
768	86,86

All but the last one run Gentoo Linux + open-vm-tools, the last one is an old redhat 7.2 system (using the vmware tools that com with Esxi).

Any help in finding out where this high Memory overhead comes from would be greatly apreciated.

Thanks, Martin

[robertortel]

Why didn't you try the original vmware tools with any of the high overhead VMs? Never heard about it but worth a try, isn't it? I cannot imagine that the root cause are the different linux distributions. What about some cachings for iscsi access? Is there much IO? Does the overhead increase over time? What are all those VMs doing?

Robert

[mabene]

Can't use the original tools - gentoo isn't a distribution recognised by vmware and the scripts don't really fit. not much IO going on - the virtual machines are low-usage webservers with just a couple 1000 hits/day. Average CPU usage for the whole system is < 500Mhz (out of 2x 2.133Ghz available.

Overhead does increase over time up; first system on the list is now up to 517,26 for example. Poweroff/restart of the VMs reduces Memory overhead to expected values.

is there any way to see what that overhead is actually getting used for?

Thanks, Martin

[robertortel]

No, I do not know a way gain a look into this overhead.

But another thing: Is it possible that the open-vm-tools are only suitable with VMWare Server, Workstation andPlayer and not with infrastructure products like ESXi? As I migrated from VMWare Server to ESXi I had to install a new version of VMWare Tools, so may be this is the reason.

Robert