Messages in this thread | | | Date | Thu, 26 Feb 2009 12:30:45 -0500 (EST) | From | Christoph Lameter <> | Subject | Re: [PATCH 20/20] Get rid of the concept of hot/cold page freeing |
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On Thu, 26 Feb 2009, Mel Gorman wrote:
> > I tried the general use of a pool of zeroed pages back in 2005. Zeroing > > made sense only if the code allocating the page did not immediately touch > > the cachelines of the page. > > Any feeling as to how often this was the case?
Not often enough to justify the merging of my patches at the time. This was publicly discussed on lkml:
http://lkml.indiana.edu/hypermail/linux/kernel/0503.2/0482.html
> Indeed, any gain if it existed would be avoiding zeroing the pages used > by userspace. The cleanup would be reducing the amount of > architecture-specific code. > > I reckon it's worth an investigate but there is still other lower-lying > fruit.
I hope we can get rid of various ugly elements of the quicklists if the page allocator would offer some sort of support. I would think that the slow allocation and freeing behavior is also a factor that makes quicklists advantageous. The quicklist page lists are simply a linked list of pages and a page can simply be dequeued and used.
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