Difference in VMware memory & Windows server memory utilization

[CallumD]

Hello, I am not sure if this has been asked before but recently I built a VM server 2008 R2 box with 4 GB RAM in VMware. Installed the server with SQL & other applications & now have about 600 MB RAM left (see attached). But if I go to VSphere > choose the client & go to daily summary I see that memory utilization is only 2 Gigs & that too sporadic (see attached). My question is why the difference? Why is VM summary not showing actual memory utilization on 2008 box? Is there something I am doing wrong or is it by design? Please help in deciphering, thanks in advance.

[JCMorrissey]

Hi Callum,

Take a look at Duncan's description of the various memory metrics for a VM, explains it very well i think.

http://www.yellow-bricks.com/2010/12/20/vcenter-and-memory-metrics/

At a host level there is a various techniques used to reclaim,provide memory to VM's on a needed basis. Elements such as transparent page sharing, memory ballooning, compression and host swapping are the main ones. Resource management guide is the reference for that piece:

http://pubs.vmware.com/vsphere-51/index.jsp?topic=%2Fcom.vmware.vsphere.resmgmt.doc%2FGUID-98BD5A8A-...

Many tx!

[CallumD]

After some research & stumbling on various blogposts, articles & videos I finally got answer to my question. What helped is a link & a VMware article, both attached to this discussion. Thanks to all & I hope this helps.

http://www.youtube.com/watch?v=uFVPN3irWfo