Re: [quad core results] BFS vs. mainline scheduler benchmarks and measurements

From: Nikos Chantziaras
Date: Mon Sep 07 2009 - 11:34:29 EST

On 09/07/2009 03:16 PM, Ingo Molnar wrote:
Note that usually we can extrapolate ballpark-figure quad and dual
socket results from 8 core results. Trends as drastic as the ones
i reported do not get reversed as one shrinks the number of cores.

Con posted single-socket quad comparisons/graphs so to make it 100%
apples to apples i re-tested with a single-socket (non-NUMA) quad as
well, and have uploaded the new graphs/results to:

kernel build performance on quad:

pipe performance on quad:

messaging performance (hackbench) on quad:

OLTP performance (postgresql + sysbench) on quad:

It shows similar curves and behavior to the 8-core results i posted
- BFS is slower than mainline in virtually every measurement.

Except for numbers, what's your *experience* with BFS when it comes to composited desktops + games + multimedia apps? (Watching high definition videos, playing some latest high-tech 3D game, etc.) I described the exact problems experienced with mainline in a previous reply.

Are you even using that stuff actually? Because it would be hard to tell if your desktop consists mainly of Emacs and an xterm; you even seem to be using Mutt so I suspect your desktop probably doesn't look very Windows Vista/OS X/Compiz-like. Usually, with "multimedia desktop PC" one doesn't mean:

but rather:

BFS probably wouldn't offer the former anything, while on the latter it does make a difference. If your usage of the "desktop" bears a resemblance to the first example, I'd say you might be not the most qualified person to judge on the "Linux desktop experience." That is not meant be offensive or patronizing, just an observation and I even might be totally wrong about it.
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