I'm running a frontend and backend Exchange 2003 server on one ESXi host. Both VM's tend to have random processing spikes. This is normal considering the frontend server is running GFI Mail Essentiails, Security, and BB Enterprise server. The backend server has 65 mailboxes connected to it and it's DB is 65 GB's. I don't mind the VM 'frontend' performing slower than normal for users are not accessing that server directly and/or interactively, however, a few times a day when the processor spikes it tends to result in Outlook clients hanging while waiting for the server to respond... Attached are snapshots of my available resources and how the CPU resources are allocated. I was wondering if I could allocate more CPU to my backend server to give my users a better experience... I'm not sure if the current config is handing the amount of CPU resource I need it to receive. I noticed the shares are at 1,000. Not sure if that's limiting my overall CPU availability.