[plt-scheme] Parallel execution

On Jan 14, 2006, at 4:12 PM, Chongkai Zhu wrote:

> PLT thread are user thread instead of kernal thread. Here is a  
> quoting:
>
> 1 Kernel threads:
> – OS is aware of “thread” abstraction
> – Each thread has separate OS state (ready, blocked,…)
> – Kernel schedules threads rather than processes
> – Kernel context switches between threads (and processes)
> 	= Thread switch: save/restore registers (inc. PC and SP)
> 	= Process switch: above plus MMU/TLB state
> 	= Thread switches cheaper than process (~10us vs ~30us)
> 2 User threads:
> – OS is unaware of “thread abstraction”
> – User-level thread library implements abstraction
> – Thread “context switch” performed entirely within user space
> – Requires cooperation between threads to ensure fairness

What are you quoting here?

===
Gregory Woodhouse
gregory.woodhouse at sbcglobal.net

"A hero is no braver than an ordinary
man, but he is brave five minutes longer."
-- Ralph Waldo Emerson