Hi there, I was wondering if it''s possible to use PSCHED_CPU (cpu cycle counter as clock source for QoS). Normally kernel menuconfig forbids it due to lack of synchronization of counters on different cpu, but: http://uwsg.iu.edu/hypermail/linux/kernel/9902.0/0053.html and quoting interesting part... ------------- checking TSC synchronization across CPUs: BIOS BUG: CPU#0 improperly initialized, has -25 usecs TSC skew! FIXED. BIOS BUG: CPU#1 improperly initialized, has 25 usecs TSC skew! FIXED. ------------- ... we can see TSC is synchronized during boot process. So, is it or is it not possible/prudent to use PSCHED_CPU on x86/x86_64, where TSCs are used? pozdrawiam, Marek Kierdelewicz