2 ms·
Of a sort. It down-prioritizes processes which were previously descheduled by timer, and up-prioritizes those which are waiting for I/O. This generally has the
by Filligree 7y ago
Of a sort. It down-prioritizes processes which were previously descheduled by timer, and up-prioritizes those which are waiting for I/O. This generally has the desired effect of prioritizing interactive work.
If you mean prioritization based on total CPU time then no, I don't think it does that, but the above does approximate prioritization based on a (very small) sliding window of CPU use.
- hinkley 7y agoI wonder if that policy is purely empirical or if the people who decided to favor I/O had a more sophisticated understanding of the system. Since a lot of algorithms have a log(n) component to them, either expressly or due to CPU physics, calling a function twice as often with half as much data may reduce call time a little bit, even a hair. I could see someone making a design decision based on a 2% disparity between two alternatives.