Could anybody share data on performance of UMDF driver vs. similar kernel driver?
For a future project, I'm considering a usermode driver, but the customer has doubts about performance impact. The device itself is quite trivial, it is (PCI) memory-mapped array of various digital sensors, A/D converters etc. These should be polled at unknown rate by unknown number of client apps. Lots of small-size requests. We can 'do the math' on the device accesses, but have difficulty to estimate effect of thread switches, caches and other such things.
Expected target machines are at least 4 cores i5-class cpu, with enough RAM.