ULE vs. 4BSD in RELENG_7

Josh Carroll josh.carroll at gmail.com
Fri Nov 2 13:13:19 PDT 2007

> Could you try spot checking a couple of tests with kern.sched.slice set to
> half its present value?  4BSD on average will use half the slice that ULE
> will by default.

The initial value was 13, and I changed it to 7. Here is the time
result for the ffmpeg run:

13:  1:39.09
7:    1:37.01

I also ran it with 4BSD again, as I think I recompiled ffmpeg since my
previous testing. It ran in:


So the difference in this workload is only 2.63% when I change the
slice value to 7. I will re-run my super-smack testing as well and
reply with the results.

> This is interesting.  I have had a couple of laptop users report success
> in using lower power saving modes with ULE.  Are these core temp
> observations repeatable?

Yes, seem to be. I notice the trend in the graphs whenever I'm booted
into the ULE kernel for long enough to see a few hours' of data.


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