Eugene, It sounds like you're doing exactly what we've been trying to achieve. We're trying to meet soft real-time deadlines that are in order of seconds (2sec). The only differences between our systems are: - kernel 2.4.20 - HZ = 100 - Compact Flash
We tried to do a similar thing to the scenario you described where we were running all other threads with SCHED_OTHER, and the thread with real-time priority with RoundRobin scheduler policy. We keep experiencing the greatest slips for such file system intensive operations like gzip and tar. Also, for an experiment, we tried to turn disk caching off, which helped meeting the deadlines a little but slowed down all file transfers unacceptably. To eliminate the question on the compact flash performance we tried using NFS. Using NFS yielded similar results (missed deadlines) to performing the transfers with the cflash card. Did you have to set anything special at your kernel config file (.config)? Did you need to apply low-latency patch separately or the MV kernel you have came pre-patched? Thanks, Adam Zajac
