3 ms·

Context switches are really fast on modern x86.

• Jweb_Guru 10y ago
  Plus there are specialized hardware instructions for them, and the expensive parts (saving weird registers etc.) are fast-pathed in Linux if they're not being used.
• toast0 10y ago
  > Context switches are really fast on modern x86. Not context switching is even faster. How fast is really fast, how modern is modern? some results from 2010 [1] show at least 1000 nanoseconds per context switch (even with optimizations for the kernel switching between threads of the same process). That's not that slow, but it is a lot of time you could be doing something else. [1] http://blog.tsunanet.net/2010/11/how-long-does-it-take-to-make-context.html http://blog.tsunanet.net/2010/11/how-long-does-it-take-to-ma... [1] http://blog.tsunanet.net/2010/11/how-long-does-it-take-to-make-context.html http://blog.tsunanet.net/2010/11/how-long-does-it-take-to-ma...