Here is another try at providing feedback to tune the vm_swappiness.
I spent some time yesterday trying to demonstrate performance improvements
from those two patches. Using
make -j4 vmlinux with mem=64m
and
qsbench -p 4 -m 96 with mem=256m
and was not able to do so, which is what I expected.
We do need more quantitative testing on this work.
Sure thing.
I need to point out a few things:
The point of this patch was to improve the swap behaviour on desktop like loads.
The fact that it improved the "when swap is thrashing" scenario (in my testing) was an unintentional bonus.
I dont think your load of j4 will induce quite the same swap thrash as what I was testing. I actually suspect the faster cpu & more jobs over fixed memory shows it more.
I need someone with more varied hardware to test it for me. I can recreate equivalent results on my current machine which has similar hardware, but I think results showing improvement on different machines and different loads is what you're looking for... and since I'm currently quite low on hardware I can only offer results from this one (and my wife is hating it being offline o_0)
Anyone willing to offer to do some tests?
What kind of mem pressure are you looking for? kernel compile is easy to run, and straight "-j" should kill a small system fairly well ... you want it just
into swap, or thrashing the crap out of it?
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