Hello,
where is the “Low thread priority” setting in Vray5?
It’s not anymore where it was and I can’t find something similar.
Is there any way to limit the number of cores, to let it render in background?
Thanks!
You can read about the “Low thread priority” option’s disappearance in this topic. Otherwise, you can limit the number of threads (cores usually have two threads, where each thread is represented by a single bucket in bucket rendering) through this environment variable:
VRAY_NUM_THREADS=N
I use Prio – Process Priority Saver.
It’s free for personal, non commercial use, or costs around 20 bucks for a single perennial license.
I personally never had issues, nor could live without it (well, unless MS implemented this in the OS itself.).
However, i’m not endorsing this: i have no affiliation to the developer, i’m just reporting my own experience. 
I blame MS. In win xp 64. You used to be able render render with the renderer set to low priority and play Quake 3 in the FG with no slow down at all. XP would properly completely starve lower priority processes if there was a higher priority process available to run. This is what the user wants on a workstation.
Now they give “fair” time to all processes, even lower priority ones, and it slows down FG work. Not good scheduler design for a workstation, IMHO.
Argh!
I hadn’t updated windows in a while, so i wouldn’t know.
I’ve currently got no idea of a substitute, unfortunately.
Maybe win 11 has a better task manager that allows for the saving of priorities and affinities?
Anyone with win 11 installed that can chime in?
Oh no, beware of Windows 11 ! 
Wait at least another year, I heard nothing good from a friend…
But why couldn’'t chaosgroup reactivate the priority management (amount of cores), which it had already integrated in the past?
Please keep me updated for any solution, thanks!
That is always active now.
However, it never fixed the issue as lowering Max’s priority did.