Oleg Galimov <Galimov <at> gmx.de> writes: > I have a dual-core cpu. When I run cyclictest on both cores and then start a time hog (like cp /dev/zero > /dev/null), then the average latency on the core where it runs goes down significantly (on my machine it is > like 30us before and 10us after, when using rt-patch). It returns to the original values, when I kill the cp process. I made a similar observation while measuring the jitter in the time of execution of usleep(). The more load the machine has the less becomes the average jitter. Of course, there is a point of inflection when the system is fully stretched. I observed this behavior on a ppc405 based embedded system (no SMP) with and without CONFIG_PREEMPT_RT. Interestingly enough, I was unable to reproduce your observation with the cyclictest tool on this system. Regards, Jens Wirth -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
