Guest OS Performance

[uofnjferrin]

I'm looking for some advice/direction on why a particular guest VM's memory is swapping and ballooning.

The guest is running Windows Server 2003 Standard Edition x64 SP2. The application on the server is SQL Server 2005 Enterprise Edition with SP3 installed. The guest is configured with 2 vCPU's, 8GB of RAM. The host it's running on is a Dell PE 2950 with 64GB of RAM. Looking at Task Manager/Perfmon in the guest nothing looks out of the ordinary other then the fact there is some paging going on. SQL Server doesn't seem to be taking more then it's fair share, at least not 8GB worth. When I look at page file usage it is 7.29GB and the physical memory is down to a little over 300MB of RAM out of the 8GB.

Here's esxtop looks like on the host with the guest vm in question outlined in red.

If I migrate the guest to another host in the same cluster the ballooning and swapping go way during the migration but come back immediately on the new host. I have un-installed and re-installed the VMWare tools on the guest.

Any advice or help anyone can provide would be appreciated.

[VMmatty · Accepted solution]

Is there a memory limit imposed on the VM? That would follow it around if you move it from one host to another.

Matt

My blog:

[uofnjferrin]

Thanks Matt. That was it. We don't do reservations or resource pools so I didn't think to look there. For whatever reason the memory limit on the VM was set to 1024MB rather than unlimited like the rest of our VM's are.

[VMmatty]

Glad that fixed it. I've seen a situation where a limit gets put into a template and then all VMs deployed end up with that limit. Might be worthwhile to check there and make sure that isn't the case.

[uofnjferrin]

Yep, this server was deployed from a tempate, so I'll be checking into that.

Thanks again.