Messages in this thread | | | Subject | Re: large page patch (fwd) (fwd) | From | (Eric W. Biederman) | Date | 10 Aug 2002 13:54:47 -0600 |
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Rik van Riel <riel@conectiva.com.br> writes:
> On 10 Aug 2002, Eric W. Biederman wrote: > > Andrew Morton <akpm@zip.com.au> writes: > > > > > > The other worry is the ZONE_NORMAL space consumption of pte_chains. > > > We've halved that, but it will still make high sharing levels > > > unfeasible on the big ia32 machines. > > > There is a second method to address this. Pages can be swapped out > > of the page tables and still remain in the page cache, the virtual > > scan does this all of the time. This should allow for arbitrary > > amounts of sharing. There is some overhead, in faulting the pages > > back in but it is much better than cases that do not work. A simple > > implementation would have a maximum pte_chain length. > > Indeed. We need this same thing for page tables too, otherwise > a high sharing situation can easily "require" more page table > memory than the total amount of physical memory in the system ;)
It's exactly the same situation. To remove a pte from the chain you must remove it from the page table as well. Then we just need to free pages with no interesting pte entries. Eric - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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