Jeroen Van den Keybus wrote: > I'm observing a considerable amount of Page Faults (5090 after an hour or > so), each one associated with a MSW increase in /proc/xenomai/stat. I'm > missing RT deadlines on those occasions and I want to fix it, so I would > like to know what Page Faults actually are. > Maybe not all of your user memory is cleanly locked and got swapped out (swapping activated?). If you don't see kernel oopses and your programs don't receive segfaults, these faults are references to swapped out or not yet mapped in pages. BTW, what does the kernel console tell you? The deadline misses as a result are "normal": your RT thread gets switched to secondary mode to handle the fault, and handling it may take some time... Jan