On Fri, 2012-05-18 at 11:00 -0500, Christoph Lameter wrote: > Having the page local is a win if there are a sufficient number of > accesses to amortize the effort to move the page. Given the expensive > nature of page migration there would need to be a large number of accesses > to a page to justify the effort. Right, but this is true of any migration scheme and not specific to MoF. > > How does it matter how you migrate? > > Migrate on fault incurs two types of costs: > > 1. Unmapping. This results in additional faults to reestablish the ptes. > > 2. Actual lazy migrate. More faults. Now the page needs to be copied to > the new node and the actual migration work is done. Nah, only the 1 fault is extra. Regular migration already needs to unmap and copy and reinstate, so the only extra work is the fault to trigger it. -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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