G io complemon or a message from or the complemon of

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Unformatted text preview: h values from that process’s PCB – general purpose registers, stack pointer, instrucFon pointer The act of switching the CPU from one process to another is called a context switch   systems may do 100s or 1000s of switches/sec.   takes a few microseconds on today’s hardware   25 May 2012 Choosing which process to run next is called scheduling Processes & Threads 9 University of Washington Process execuFon states  Each process has an execuFon state, which indicates what it’s currently doing   ready: waiMng to be assigned to a CPU could run, but another process has the CPU   running: execuMng on a CPU   it’s the process that currently controls the CPU   waiMng (aka “blocked”): waiMng for an event, e.g., I/O compleMon, or a message from (or the compleMon of) another process   cannot make progress unMl the event happens     As a process executes, it moves from state to state   UNIX: run p...
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