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SubjectRe: 2.2.5 optimizations for web benchmarks?
Hi,

On Mon, 26 Apr 1999 19:08:36 -0400 (EDT), Greg Lindahl
<lindahl@cs.virginia.edu> said:

>> If you are sharing the virtual memory space it means you don't take
>> a TLB flush

> If I recall correctly, the Sybase folks described this as a major win
> across many OSes. On the other hand, Apache in particular may not
> access enough memory to make a huge difference.

Remember, this is TLB flushes, not cache flushes, we're talking about.
*Every* memory access after a TLB flush needs to reload the TLB, even if
it is just a read from already-cached memory. Even just spinning in
kernel space may require TLB refills after a flush (although newer
Pentia do let you mark certain page tables as global, so a mm replace
won't evict those TLBs).

--Stephen

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