ULE vs. 4BSD in RELENG_7

[Josh Carroll]

> My next step is to run some transcodes with mencoder to see if it has
> similar performance between the two schedulers. When I have those
> results, I'll post them to this thread.

mencoder is linked against the same libx264 library that ffmpeg uses
for h.264 encoding, so I was expecting similar results as ffmpeg.
However, the results are slightly different:

4BSD (threads=2):       93.82 real       182.82 user         0.30 sys
4BSD (threads=3):       64.79 real       184.27 user         0.41 sys
4BSD (threads=4):       51.36 real       185.76 user         0.31 sys
4BSD (threads=5):       49.88 real       186.11 user         0.24 sys
4BSD (threads=6):       49.53 real       186.28 user         0.32 sys
4BSD (threads=7):       49.45 real       186.32 user         0.33 sys
4BSD (threads=8):       49.36 real       186.39 user         0.34 sys

ULE (threads=2):       92.81 real       182.41 user         0.36 sys
ULE (threads=3):       64.28 real       184.57 user         0.39 sys
ULE (threads=4):       56.83 real       185.83 user         0.32 sys
ULE (threads=5):       55.30 real       185.95 user         0.42 sys
ULE (threads=6):       55.38 real       186.12 user         0.45 sys
ULE (threads=7):       55.24 real       186.14 user         0.60 sys
ULE (threads=8):       55.08 real       186.28 user         0.52 sys

What's interesting is that for threads=2 and threads=3, ULE and 4BSD
are performing the same.  After that, though, there's a 10% gap for
the remaining data points. Also interesting is that they both reach a
plateau at threads=5. I suppose this means mencoder is more efficient
than ffmpeg? Anyway, ULE is still 10% slower with mencoder, which is
"worse" than the 5% drop with ffmpeg.

I decided to run pbzip2 also. The -p argument doesn't seem to
necessarily create as many threads as you request (or it's completely
I/O bound):

4BSD(-p 4):       30.91 real       117.32 user         4.67 sys
4BSD(-p 5):       31.45 real       119.49 user         5.02 sys
4BSD(-p 6):       31.85 real       120.42 user         5.49 sys
4BSD(-p 7):       31.55 real       119.16 user         5.59 sys
4BSD(-p 8):       31.92 real       120.29 user         5.81 sys

ULE(-p 4):       33.73 real       114.60 user         4.51 sys
ULE(-p 5):       31.57 real       116.80 user         5.18 sys
ULE(-p 6):       31.74 real       118.00 user         5.21 sys
ULE(-p 7):       32.04 real       118.32 user         5.39 sys
ULE(-p 8):       32.35 real       120.22 user         6.05 sys

ULE is slightly slower here with -p4 (9.12 %) and -p8 (1.35 %), but
about the same for 5-7.

Hope this helps,
Josh