VCP5 – Enable/Size/Disable memory compression cache

Memory compression uses standard compression techniques (like ZIP or RAR) to extend the use of RAM instead of swapping to disk. Compression is enabled by default and improves performance when over-committing memory by limiting the amount of swap-to-disk, a process that can take considerable time.

Enabling/Disabling Memory Compression

1. Open the Virtual Center and select Hosts and Clusters
2. Select a host and click the Configuration tab
3. Select Software | Advanced Settings
4. Select Mem.MemZipEnable, 1 for on, 0 for off

1. Open the Virtual Center and select Hosts and Clusters
2. Select a host and click the Configuration tab
3. Select Software | Advanced Settings
4. Select Mem.MemZipMaxPct
1. This defaults at 10% of the RAM for caching and can be altered from 5% to 100%

http://pubs.vmware.com/vsphere-50/index.jsp?topic=/com.vmware.vsphere.vcenterhost.doc_50/GUID-E1D90120-73EB-4B00-9F89-8650EBE911F7.html