We have VC 4.1 Build 345043 running as a VM in a 4 hosts single cluster. DRS is manual. Operating System for VC is Windows 2008 R2. 2 vCPU and 8GB RAM is allocated. Within an hour or two vpxd sucks all the memory and as the day goes by the system becomes slow or unresponsive.
Number of VMs in the cluster: 125. There isn't anything else we are doing in the environment. I found an old thread on memory leak but it was more focussed on older VC version and had very few posts on 4.1.