[DCP-o-matic] How to use dcpomatic.

Hello! We need use the dcpomatic on a virtual servers. We have a server with two processors, and when we start coding with dcpomatic on one virtual server it works fast. When we start encoding with dcpomatic on two virtual servers at the same time it works slow. Dcpomatic don't use a second proccesor. Help us, say how to setup dcpomatic for use on two virtual servers, please. With best regards, Boris.