1. A computer network comprising: a network; a first host system coupled to said network, said first host system comprising a host machine and a virtual machine installed on said host machine; a second host system coupled to said network, said second host system comprising a host machine and a virtual machine installed on said host machine; and a virtual input/output channel (VIOC) system associated with at least one of said first and second host systems, said VIOC system comprising virtual I/O channels (VIOCs) and a VIOC agent, said VIOCs including multiple, variable size I/O data queues from which I/O requests generated by said virtual machines may be serviced, and wherein said VIOC agent is configured to adaptively manage I/O data queues within said VIOCs.