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

Manipulate Scheduling Parameters: thread_schedule System Call

• Allows setting/inquiring the priority and timeslice length of a thread.
• Also returns thread state (running/IPC-ing/dead).
  • Partially implemented on MIPS.
• Scheduling parameters can only be changed for a thread running at a
  lower priority than the caller's maximum controlled priority (MCP).
• If setting priority, cannot exceed caller's MCP.
• MCP is task attribute, specified in task_create system call
  (child MCP cannot exceed parent's).