Messages in this thread | | | Date | Mon, 13 Sep 2004 14:53:58 +1000 | From | Nick Piggin <> | Subject | Re: 2.6.9-rc1: page_referenced_one() CPU consumption |
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Nikita Danilov wrote:
> I ran tests few times, and difference between patched and un-patched > kernels is within noise, so you are right, try-lock does not help. >
Well I'm glad - because I much prefer the spin_lock over the trylock :)
> But now I have new great idea instead. :) > > I think page_referenced() should transfer dirtiness to the struct page > as it scans pte's. Basically the earlier we mark page dirty the better > file system write-back performs, because page has more chances to be > bulk-written by ->writepages(). This is better than my previous patches > to this end (that used separate function to transfer dirtiness from > pte's to the page), because > > - locking overhead is avoided > > - it's simpler. > > Nick, are you still in business of benchmarking random VM patches? :-) >
Yeah I am, and I do have that patch sitting around. It can *really* help for writeout via maped memory (obviously doesn't help write()).
I think Andrew's response was that it can theoretically cause writeout for workloads that don't want it, so I should come up with at least one real-world improvement! - 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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