Re: page fault scalability patch v3: use cmpxchg, make rss atomic

Matthew Wilcox
2004-08-24T12:34:16Z

On Mon, Aug 23, 2004 at 10:49:31PM -0700, Christoph Lameter wrote:
> Unpatched:
> Gb Rep Threads User System Wall flt/cpu/s fault/wsec
> 4 3 1 0.157s 11.197s 11.035s 69261.721 69239.940
> 4 3 2 0.145s 11.445s 6.079s 67849.528 115681.409
> 4 3 4 0.182s 13.894s 4.027s 55865.834 184108.856
> 4 3 8 0.196s 24.874s 4.025s 31369.039 184790.767
>
> With page fault scalability patch:
> Gb Rep Threads User System Wall flt/cpu/s fault/wsec
> 4 3 1 0.176s 11.323s 11.050s 68385.368 68345.055
> 4 3 2 0.174s 10.716s 5.096s 72205.329 131848.322
> 4 3 4 0.170s 10.694s 3.040s 72380.552 231128.569
> 4 3 8 0.177s 14.717s 2.064s 52796.567 297380.041

What kind of variance are you seeing with this benchmark? I'm suspicious
that your 2 thread case is faster than your single thread case.

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