VMWare memory allocation recommendation for 50% utilization

Hi All,

I have read in VMWare related white papers that VMWare recommends for servers to have 50% utilization of memory. Greater than 50% of memory utilization we may face latency issues since balooning will be less used. I checked with the infrastructure team in my project, they also confirmed that they are using only 50% of the available memory but they dont know the reason.

I would like to know whether what I heard VMWare recommendation is fact and the reason behind it.

I am talking about ESX 3.0 hypervisor.

Pages where I referred are,

http://www.virtualinstruments.com/files/pdfs/WP_VMware_Storage_Whitepaper.pdf

http://pubs.vmware.com/view-50/topic/com.vmware.ICbase/PDF/view-50-administration.pdf

Can someone please guide me?

Thanks and regards,

Rengasami Ramanujam