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Re: hugepage patches



> O.k.  Then the code definitely needs to handle shared mappings..

Why? we just divided the pagetable size by a factor of 1000, so
the problem is no longer really there ;-)
 
>> Well, in theory there's some kind of TLB benefit, but the only thing
>> ppl really care about is x86 pagetable structure gets rid of L3 space
>> entirely so you don't burn 12+GB of L3 pagetables for appserver loads.
> 
> I am with the group that actually cares more about the TLB benefit.
> For HPC loads there is really only one application per machine.  And with
> just one page table, the only real advantage is the more efficient use
> of the TLB.  

The reason we don't see it much is that we mostly have P3's which only
have 4 entries for large pages. P4's would be much easier to demonstrate
such things on, and I don't think we've really tried very hard on that with
hugetlbfs (earlier Java work by the research group showed impressive
improvements on an earlier implementation).

M.

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