SCHED_ULE should not be the default

[Mike Tancsa]

On 12/13/2011 10:54 AM, Steve Kargl wrote:
> 
> I have given the WHY in previous discussions of ULE, based
> on what you call legacy benchmarks.  I have not seen any
> commit to sched_ule.c that would lead me to believe that
> the performance issues with ULE and cpu-bound numerical
> codes have been addressed.  Repeating the benchmark would
> be a waste of time.

Trying a simple pbzip2 on a large file, the results are pretty
consistent through iterations. pbzip2 with 4BSD is barely faster on a
file thats 322MB in size.

after a reboot, I did a
strings bigfile > /dev/null
then ran
 pbzip2 -v xaa -c > /dev/null
7 times

If I do a burnP6 in the background, they perform about the same.

(from sysutils/cpuburn)
eg

 pbzip2 -v xaa -c > /dev/null
Parallel BZIP2 v1.1.6 - by: Jeff Gilchrist [http://compression.ca]
[Oct. 30, 2011]               (uses libbzip2 by Julian Seward)
Major contributions: Yavor Nikolov <nikolov.javor+pbzip2 at gmail.com>

         # CPUs: 4
 BWT Block Size: 900 KB
File Block Size: 900 KB
 Maximum Memory: 100 MB
-------------------------------------------
         File #: 1 of 1
     Input Name: xaa
    Output Name: <stdout>

     Input Size: 352404831 bytes
Compressing data...
    Output Size: 50630745 bytes
-------------------------------------------

     Wall Clock: 18.139342 seconds


ULE
18.113204
18.116896
18.123400
18.105894
18.163332
18.139342
18.082888

ULE with burnP6
23.076085
22.003666
21.162987
21.682445
21.935568
23.595781
21.601277


4BSD
17.983395
17.986218
18.009254
18.004312
18.001494
17.997032

4BSD with burnP6
22.215508
21.886459
21.595179
21.361830
21.325351
21.244793



# ministat uleP6 bsdP6
x uleP6
+ bsdP6
+------------------------------------------------------------------------------------------------------------------------------------------+
|x    +   + +            +    x           +  x  x           +
                                     x                            x|
|
|____|______________MA____________________|M_____________A__________________________________________________|
                        |
+------------------------------------------------------------------------------------------------------------------------------------------+
    N           Min           Max        Median           Avg        Stddev
x   6     21.162987     23.595781     22.003666     22.242755    0.91175566
+   6     21.244793     22.215508     21.595179     21.604853     0.3792413
No difference proven at 95.0% confidence



x ule
+ bsd
+------------------------------------------------------------------------------------------------------------------------------------------+
|+ +       +   + +   +
     x                x     x  x    x           x                 x|
|   |______A___M___|
              |________________M__A__________________|             |
+------------------------------------------------------------------------------------------------------------------------------------------+
    N           Min           Max        Median           Avg        Stddev
x   7     18.082888     18.163332     18.116896     18.120708   0.025468695
+   6     17.983395     18.009254     18.001494     17.996951   0.010248473
Difference at 95.0% confidence
        -0.123757 +/- 0.024538
        -0.68296% +/- 0.135414%
        (Student's t, pooled s = 0.0200388)





hardware is X3450 with 8G of memory.  RELENG8

	---Mike


-- 
-------------------
Mike Tancsa, tel +1 519 651 3400
Sentex Communications, mike at sentex.net
Providing Internet services since 1994 www.sentex.net
Cambridge, Ontario Canada   http://www.tancsa.com/