With the development of reconfigurable computers containing FPGAs with in excess of 6 million system-gates, it is now feasible to consider the possibility of sharing the FPGA between multiple concurrently executing applications. This could potentially increase the resource usage of the expensive FPGA logic and decrease response times so users will not have to wait for the FPGA to be completely available. However the system environment software required to support this, may actually result in application performance much less than would be considered acceptable to many FPGA users. This paper involves using a prototype to evaluate the performance of such an operating system, ReconfigME