I'm writing a a very small daemon that must remain responsive even when a system is under severe stress. I'm looking at the differences between SCHED_FIFO and SCHED_RR in regards to scheduling, as well as trying to determine a sensible priority.
Which scheduler would be appropriate for a small but critical monitoring daemon, what priority would be reasonably safe? I'm still coming up a little fuzzy when trying to understand the differences between the two.
My program is allocating under 3k (and uses mlockall()), it writes about 600 bytes to xenbus then sleeps, but its impossible for me to tell how much time (in ms) it will take to actually write the data.. since what is written depends on a configuration file.
Thanks in advance for any suggestions / explanations.