School of Computer Science & Engineering
University of New South Wales
Advanced Operating Systems
COMP9242 2002/S2

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Release CPU: thread_switch System Call

The calling thread voluntarily releases the CPU.

May specify another thread to continue immediately
(``time slice donation'').
- Destination thread gets remaining time slice ``for free''.
- Normal scheduling taken at expiry.
May yield CPU by not specifying valid destination thread.
- Remaining time thread is forfeit.
- Normal scheduling action taken immediately
  (possibly re-scheduling caller thread).

Gernot Heiser 2002-08-07