3 ms·
need no, but it could be useful. Not a requirement, but a very “nice to have” property. It would reduce certain confusions in some end users, as well as being h
by dspillett 2y ago
need no, but it could be useful. Not a requirement, but a very “nice to have” property. It would reduce certain confusions in some end users, as well as being handy for us techie types.
Often you don't care that the current batch of processes are using 100% of what the CPU cores they are assigned to can do at current clock rates, what you want to know is how much is left available, so you can add more work without slowing any existing tasks down much.
It used to be, back when CPUs didn't have low & high power cores and always ran what they had at the same speed, that %CPU shown in various OS displays was a reasonably accurate measure of the impact of a process that could easily be used to judge optimisation success (getting the same done in less hardware effort) and scaling success (getting the same done in less wall-clock time by giving more hardware to the problem or improving parallelism to make better use of what you already have).
These days it is more complicated than most assume at face value, and you have to be a lot more careful when assessing such things to avoid incorrect assumptions leading to wrong decisions. It would be nice to get back to the previous state of affairs, in terms of a given % value meaning something more fixed. Of course that is not as practical to achieve as naively stating the problem might suggest: for a start you can't really state what 100% is because in many cases the maximum clock might only be achievable for very short periods before thermal throttling kicks in. Maybe if there is a “minimum maximum”, below which we know the throttle won't go, we could state that as 100% and display more when the heat limit is not taking effect, but I expect that really would confuse end users (I have memories of confused conversations when multi-core CPUs became common, when people saw displays of processes using ~200%, with that meaning ~100% of ~2 cores).