I honestly dont understand why none of the main consumer operating systems are optimized for low latency. outside servers, I feel like I would gladly take an OS that made my computer 2x slower, but never had a pause of more than half a ms or so.
A while after OpenZFS implememted ZSTD compression I started using it for backups, opting for the highest level of compression and scheduling it very early in the morning so it'd run when I wasn't by the PC when it ran.
Occasionally I'd be awake around then anyway, and I would experience 5-30second UI-freezes.
After fiddling around a bit I decided to try the MuQSS CPU scheduler and was blown away. Not only was the scheduled backup unnoticeable, on top of that I could throw a 16 thread compilation job on my 8core/16thread CPU and I'd not notice the system being under load. I might've lost a few frames per secone when occasionally playing some FPS games, but possibly lowered throughput be damned, this was bliss.
Unfortunately it seems to not be updated anymore. So I tried the newcomers on the block, BMQ and PDS. With BMQ I would start dropping iSCSI connections since my PC wouldn't manage to reply to a ping in five seconds. PDS fit better. While MuQSS could handle a load of 40-45 before I started noticing UI-latency, PDS tops off at around 20. And when it starts to stutter, it's worse than with MuQSS, but since it's not that often that I'm at those loads I'm quite OK with the current situation.
All this with untuned schedulers, they might behave very differently with some tuning.
Half a millisecond is 20 samples missed. 44000 * .0005 = 22
But that's not what he meant, he meant that non-real time (soft real time, not even hard real time) OSs pause pretty frequently for relatively long periods. You might not miss any samples at all due to hardware buffering, but the effect on UI is tremendous.
