On Fri, Oct 21, 2011 at 12:05:30AM +0800, Wu Fengguang wrote: > Trond, > > After applying these two patches, the IO-less patchset performances > 45% better than the vanilla kernel and the average commit size only > decreases by -16% in the common NFS-thresh=1G/nfs-1dd case :) To better understand how the NFS writeback wait queue helps, I visualized the network traffic over time. Attached are the graphs for the vanilla kernel and the one with the IO-less + NFS wait queue patches. nfs-1dd-4k-32p-32016M-1024M:10-3.1.0-rc8-vanilla+/dstat-bw.png nfs-1dd-4k-32p-31951M-1024M:10-3.1.0-rc8-nfs-wq4+/dstat-bw.png The obvious difference is, the network traffic become now more distributed and the "zero traffic" periods are mostly reduced. The other 2dd, 10dd cases have similar results. Thanks, Fengguang
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dstat-bw.png
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dstat-bw.png
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