Re: [PATCH 0/18] Basic scheduler support for automatic NUMAbalancing V5

[Peter Zijlstra]

On Mon, Jul 15, 2013 at 04:20:02PM +0100, Mel Gorman wrote:
> 
> specjbb
>                         3.9.0               3.9.0                 3.9.0                 3.9.0
>                       vanilla          accountload-v5       retrymigrate-v5          swaptasks-v5  
> TPut 1      24474.00 (  0.00%)      24303.00 ( -0.70%)     23529.00 ( -3.86%)     26110.00 (  6.68%)
> TPut 7     186914.00 (  0.00%)     179962.00 ( -3.72%)    183667.00 ( -1.74%)    185912.00 ( -0.54%)
> TPut 13    334429.00 (  0.00%)     327558.00 ( -2.05%)    336418.00 (  0.59%)    334563.00 (  0.04%)
> TPut 19    422820.00 (  0.00%)     451359.00 (  6.75%)    450069.00 (  6.44%)    426753.00 (  0.93%)
> TPut 25    456121.00 (  0.00%)     533432.00 ( 16.95%)    504138.00 ( 10.53%)    503152.00 ( 10.31%)
> TPut 31    438595.00 (  0.00%)     510638.00 ( 16.43%)    442937.00 (  0.99%)    486450.00 ( 10.91%)
> TPut 37    409654.00 (  0.00%)     475468.00 ( 16.07%)    427673.00 (  4.40%)    460531.00 ( 12.42%)
> TPut 43    370941.00 (  0.00%)     442169.00 ( 19.20%)    387382.00 (  4.43%)    425120.00 ( 14.61%)
> 
> It's interesting that retrying the migrate introduced such a large dent. I
> do not know why at this point.  Swapping the tasks helped and overall the
> performance is all right with room for improvement.

I think it means that our direct migration scheme is creating too much
imbalance and doing it more often results in more task movement to fix
it up again, hindering page migration efforts to settle on a node.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/