Messages in this thread | | | Date | Fri, 2 Mar 2007 17:28:18 +0000 | Subject | Re: The performance and behaviour of the anti-fragmentation related patches | From | (Mel Gorman) |
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On (02/03/07 09:19), Christoph Lameter didst pronounce: > On Fri, 2 Mar 2007, Mel Gorman wrote: > > > However, if that is objectionable, I'd at least like to see zone-based patches > > go into -mm on the expectation that the memory hot-remove patches will be > > able to use the infrastructure. It's not ideal for hugepages and it is not my > > first preference, but it's a step in the right direction. Is this reasonable? > > I still think that the list based approach is sufficient for memory > hotplug if one restricts the location of the unmovable MAX_ORDER chunks > to not overlap the memory area where we would like to be able to remove > memory.
Yes, true. In the part where I bias placements of unmovable pages at lower PFNs, additional steps would need to be taken. Specifically, the lowest block MAX_ORDER_NR_PAGES used for movable pages would need to be reclaimed for unmovable allocations.
> In very pressing memory situations where we have too much > unmovable memory we could dynamically disable memory hotplug. There > would be no need for this partitioning and additional zones. >
It's simply more complex. I believe it's doable. The main plus going for the zone is that it is a clearly understood concept and it gives hard guarantees.
-- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab - 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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