Messages in this thread | | | Date | Mon, 16 Jul 2007 15:31:18 -0500 | From | Matt Mackall <> | Subject | Re: [PATCH] CFS: Fix missing digit off in wmult table |
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On Mon, Jul 16, 2007 at 04:01:17PM +0200, Roman Zippel wrote: > Hi, > > On Mon, 16 Jul 2007, Ingo Molnar wrote: > > > to sum it up: a nice +19 task (the most commonly used nice level in > > practice) gets 9.1%, 3.9%, 3.1% of CPU time on the old scheduler, > > depending on the value of HZ. This is quite inconsistent and illogical. > > You're correct that you can find artifacts in the extreme cases, it's > subjective whether this is a serious problem. > It's nice that these artifacts are gone, but that still doesn't explain > why this ratio had to be increase that much from around 1:10 to 1:69.
More dynamic range is better? If you actually want a task to get 20x the CPU time of another, the older scheduler doesn't really allow it.
Getting 1/69th of a modern CPU is still a fair number of cycles. Nevermind 1/69th of a machine with > 64 cores.
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