4 ms·
have you actually checked that your claim tends to be true? n cores going almost n times faster with presumably some fixed overhead from the computer and threa
by gameswithgo 6y ago
have you actually checked that your claim tends to be true? n cores going almost n times faster with presumably some fixed overhead from the computer and threading might come out ahead
- FartyMcFarter 6y agoI said "in the same wall-clock time". If threading is done well, it will reduce wall-clock time, so I agree that threading could come out ahead. What I was trying to get at is that if two languages perform the same task, but one of them uses multi-threading to accomplish it, "wall-clock time" is extremely likely to be a misleading proxy for power consumption. It boils down to the fact that a CPU using all of its cores uses more power than a CPU using only one of its cores. This is easily checkable by listening to the fans on a fully loaded desktop PC, or by using software like "Core Temp" which can display CPU power consumption on some CPU models.
- jmgao 6y ago> It boils down to the fact that a CPU using all of its cores uses more power than a CPU using only one of its cores. This is true if your cores are all the same and running at the same frequency, but voltage/frequency scaling make things more complicated and heterogenous cores like in essentially every modern ARM processor completely destroy it. If you have a bunch of slow cores that are half as fast but use a quarter of the power [1], using threads to split up the work so you can still meet your deadline can definitely save power. 1: https://www.semanticscholar.org/paper/Power-aware-task-scheduling-for-big.LITTLE-mobile-Yu-Han/6f58170813145d30668521e9cbd6e71758cbbedb/figure/0 https://www.semanticscholar.org/paper/Power-aware-task-sched...
- deleted 6y ago[deleted]