Scheduler benchmarks - a follow-up

["Rob Hussey" <robjhussey@gmail.com>]

Hi all,

After posting some benchmarks involving cfs
(http://lkml.org/lkml/2007/9/13/385), I got some feedback, so I
decided to do a follow-up that'll hopefully fill in the gaps many
people wanted to see filled.

This time around I've done the benchmarks against 2.6.21, 2.6.22-ck1,
and 2.6.23-rc6-cfs-devel (latest git as of 12 hours ago). All three
.configs are attached. The benchmarks consist of lat_ctx and
hackbench, both with a growing number of processes, as well as
pipe-test. All benchmarks were also run bound to a single core.

Since this time there are hundreds of lines of data, I'll post a
reasonable amount here and attach the data files. There are graphs
again this time, which I'll post links to as well as attach.

I'll start with some selected numbers, which are preceded by the
command used for the benchmark.

for((i=2; i < 201; i++)); do lat_ctx -s 0 $i; done:
(the left most column is the number of processes ($i))

	2.6.21		2.6.22-ck1	2.6.23-rc6-cfs-devel

15	5.88		4.85		5.14
16	5.80		4.77		4.76
17	5.91		4.84		4.92
18	5.79		4.86		4.83
19	5.89		4.94		4.93
20	5.78		4.81		5.13
21	5.88		5.02		4.94
22	5.79		4.79		4.84
23	5.93		4.86		5.05
24	5.73		4.76		4.90
25	6.00		4.94		5.19

for((i=1; i < 100; i++)); do hackbench $i; done:

	2.6.21  	2.6.22-ck1	2.6.23-rc6-cfs-devel

80	9.75		 8.95		 9.52
81	11.54		8.87		9.57
82	11.29		8.92		9.67
83	10.76		8.96		9.82
84	12.04		9.20		9.91
85	11.74		9.39		10.09
86	12.01		9.37		10.18
87	11.39		9.43		10.13
88	12.48		9.60		10.38
89	11.85		9.77		10.52
90	13.78		9.76		10.65

pipe-test:
(the left most column is the run #)

	2.6.21	2.6.22-ck1	2.6.23-rc6-cfs-devel

1	13.84	12.59		13.01
2	13.90 	12.57 		13.00
3	13.84 	12.62 		13.06
4	13.87 	12.61 		13.04
5	13.82 	12.62 		13.03
6	13.86 	12.60 		13.02
7	13.85 	12.61 		13.02
8 	13.88 	12.45 		13.04
9	13.83 	12.46 		13.03
10	13.88 	12.46 		13.03

Bound to Single core:

for((i=2; i < 201; i++)); do lat_ctx -s 0 $i; done:

		2.6.21		2.6.22-ck1	2.6.23-rc6-cfs-devel

15		2.90		2.76		2.21
16		2.88		2.79		2.36
17		2.87		2.77		2.52
18		2.86		2.78		2.66
19		2.89		2.72		2.81
20		2.87		2.72		2.95
21		2.86		2.69		3.10
22		2.88		2.72		3.26
23		2.86		2.71		3.39
24		2.84		2.72		3.56
25		2.82		2.73		3.72


for((i=1; i < 100; i++)); do hackbench $i; done:

		2.6.21		2.6.22-ck1	2.6.23-rc6-cfs-devel

80		14.29		10.86		12.03
81		14.40		11.25		12.17
82		15.00		11.42		12.33
83		14.87		11.12		12.51
84		15.37		11.42		12.66
85		15.75		11.68		12.79
86		15.64		11.95		12.95
87		15.80		11.64		13.12
88		15.70		11.91		13.25
89		15.10		12.19		13.42
90		16.24		12.53		13.54

pipe-test:

	2.6.21	2.6.22-ck1	2.6.23-rc6-cfs-devel

1  	9.27	8.50 		8.55
2  	9.27	8.47 		8.55
3  	9.28	8.47 		8.54
4  	9.28	8.48 		8.54
5  	9.28	8.48 		8.54
6  	9.29	8.46 		8.54
7  	9.28	8.47 		8.55
8  	9.29	8.47 		8.55
9  	9.29	8.45 		8.54
10 	9.28	8.46 		8.54

Links to the graphs (the .dat files are in the same directory):
http://www.healthcarelinen.com/misc/benchmarks/lat_ctx_benchmark2.png
http://www.healthcarelinen.com/misc/benchmarks/hackbench_benchmark2.png
http://www.healthcarelinen.com/misc/benchmarks/pipe-test_benchmark2.png
http://www.healthcarelinen.com/misc/benchmarks/BOUND_lat_ctx_benchmark2.png
http://www.healthcarelinen.com/misc/benchmarks/BOUND_hackbench_benchmark2.png
http://www.healthcarelinen.com/misc/benchmarks/BOUND_pipe-test_benchmark2.png

The only analysis I'll offer is that both sd and cfs are improvements,
and I'm glad that there is a lot of work being done in this area of
linux development. Much respect to Con Kolivas, Ingo Molnar, and Roman
Zippel, as well all the others who have contributed.

Any feedback is welcome.

Regards,
Rob

Attachment: BOUND_hackbench_benchmark2.png
Description: PNG image

Attachment: BOUND_lat_ctx_benchmark2.png
Description: PNG image

Attachment: BOUND_pipe-test_benchmark2.png
Description: PNG image

Attachment: hackbench_benchmark2.png
Description: PNG image

Attachment: lat_ctx_benchmark2.png
Description: PNG image

Attachment: pipe-test_benchmark2.png
Description: PNG image

Attachment: data_files.tar.bz2
Description: BZip2 compressed data

Attachment: config-2.6.21.bz2
Description: BZip2 compressed data

Attachment: config-2.6.22-ck1.bz2
Description: BZip2 compressed data

Attachment: config-2.6.23-rc6-cfs-devel.bz2
Description: BZip2 compressed data