Re: [PATCH 1/3] mm, numa: rework do_pages_move

From: Anshuman Khandual
Date: Fri Jan 05 2018 - 04:20:26 EST


On 01/05/2018 02:44 PM, Michal Hocko wrote:
> On Fri 05-01-18 09:22:22, Anshuman Khandual wrote:
> [...]
>> Hi Michal,
>>
>> After slightly modifying your test case (like fixing the page size for
>> powerpc and just doing simple migration from node 0 to 8 instead of the
>> interleaving), I tried to measure the migration speed with and without
>> the patches on mainline. Its interesting....
>>
>> 10000 pages | 100000 pages
>> --------------------------
>> Mainline 165 ms 1674 ms
>> Mainline + first patch (move_pages) 191 ms 1952 ms
>> Mainline + all three patches 146 ms 1469 ms
>>
>> Though overall it gives performance improvement, some how it slows
>> down migration after the first patch. Will look into this further.
>
> What are you measuring actually? All pages migrated to the same node?

The mount of time move_pages() system call took to move these many
pages from node 0 to node 8. Yeah they migrated to the same node.

> Do you have any profiles? How stable are the results?

No, are you referring to perf record kind profile ? Results were
repeating.