You can set the maximum size of the memory compression cache for the host's virtual machines.
You set the size of the compression cache as a percentage of the memory size of the virtual machine. For example, if you enter 20 and a virtual machine's memory size is 1000 MB, ESXi can use up to 200MB of host memory to store the compressed pages of the virtual machine.
If you do not set the size of the compression cache, ESXi uses the default value of 10 percent.