Messages in this thread | | | Date | Thu, 12 Oct 2006 14:29:20 -0400 | From | John Richard Moser <> | Subject | Re: Can context switches be faster? |
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Phillip Susi wrote: > John Richard Moser wrote: >> Can context switches be made faster? This is a simple question, mainly >> because I don't really understand what happens during a context switch >> that the kernel has control over (besides storing registers). >> > > Besides saving the registers, the expensive operation in a context > switch involves flushing caches and switching page tables. This can be > avoided if the new and old processes both share the same address space. >
i.e. this can be avoided when switching to threads in the same process.
How does a page table switch work? As I understand there are PTE chains which are pretty much linked lists the MMU follows; I can't imagine this being a harder problem than replacing the head. I'd imagine the head PTE would be something like a no-access page that's not really mapped to anything so exchanging it is pretty much exchanging its "next" pointer?
> >
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