Multi Core Fix?

[W. Kerman]

I run KSP on my dad's computer, (mac), which has a nice intel 4-core processor. However, KSP is only using one.  

 

Does anyone know how to disable this cap?

[omelaw]

unless devs make entirely new physics system for it, no.

[Kerbal101]

Since 1.1.x, the KSP physics is multicore. Its using all four cores on my machine (8 in HT), but the one core locked into renderer, which causes fps reduction from 2000+ parts craft.
Thus, if you notice too high CPU usage of one core in 1.1.x+, this probably means you have inefficient/bottlenecking GPU and you might consider upgrading it.
(speculations)The next step is probably possible when Unity moves to Vulcan.(/speculations)