[Jobs][Lags] JobTempAlloc has allocations that are more than 4 frames old

[timjohansson]

@dyox

Maybe also clarify why 4 frames old is important.
We must count each frame and call job.complete on main thread.
So it’s totally useless and laggy to have this sort of multithreading.
At 120 fps, 4 frames is too short for jobs. 120 fps → job.complete()-> lag…

Actual system works and keep the fps stable even at 95% of cpu usage.
When using System.Thread at only 50% cpu usage, spikes and lags appear .
(8 cpu core example : 7 jobs+render thread+main thread + 7 System.Thread).
Maybe just open jobs and let user decide what to do with them.

So far we have been focusing on using all cores for the simulation rather than making it asynchronous - which means you almost always complete the job within 1 frame. The 4 frame limit comes from the fact that we are using a specialized allocator for this case, not that we actively try to limit anything.
Long running asynchronous jobs are slightly different and require some tweaking, but allowing you to choose a different allocator for such jobs which does not have to complete within 4 frames seems like a good start.