What is context switching?

[watermelonyu]

什麼時候會有context switching?

[watermelonyu]

Hi :



Context switch 的時機有二:

1. force context switch

Process run out of time slot, timeslice/Hz ( 100 ms by default) and higher priority process is waiting for CPU.

2. voluntary context switch

Process went to sleep, such as wait for I/O.



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[watermelonyu]

1. timeslice 是可由 kernal parameter 設定嗎?

2. 我們是否可得知系統實際每秒做了多少次 context switch (avg)?

[watermelonyu]

1. Kernal parameter : timeslice

2. glance or gpm(xmode) --> C for cpu report and then you can see the "ContextSwitch" by "Current Average High Time Cum Time"