SIGs/PowerManagement/RHEL5xF12comparison

RHEL 5 x Fedora 12

This is the first power consumption comparison of RHEL 5 and Fedora 12 (incoming RHEL 6). The results was measured by BLTK that gets power consumption data from laptop's battery info. There were used three workloads for this comparison:

Idle - simulates no interaction from user side (no screen saver defined)
Office - simulates working in Open Office with breaks
Reader - simulates reading text in Firefox

Used Hardware and OS

Laptop

LENOVO ThinkPad T61
* CPU Intel Core2 Duo CPU T7500 2.20 GHz
* Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller
* LCD 15" 1680x1050x24
* Memory 2 GB
* HDD 100 GB
* Battery designed and usable capacity 56.16 Wh

RHEL 5

Kernel release 2.6.18-164.el5

Fedora 12

Kernel release 2.6.31-33.fc12.x86_64

Test description

The tests were done on laptop installed with RHEL 5, Fedora 11 and Fedora 12 using shared /home. The workload mentioned above was used with following specification:

Idle test - test was running for 10 minutes

bltk -I -T 600

Office test - Open Office workload was running with three repetitions (work simulation repeated 3x)

bltk -O -n 3

Reader test - Each of tests was running also with three repetitions. Firefox is a reader application by default (bltk.conf).

bltk -R -n 3

Result tables and charts

Idle workload

RHEL 5

CPU1			CPU2			HDD					BAT begin		BAT end		Drain	BAT life
Tmr	Irq	Load %	Tmr	Irq	Load %	Rd	Wr	Act	StnBy	Slp	[mWh]	[%]	[mWh]	[%]	[W]	[min]
1000.01	0.07	0.19	0	17.59	0.39	0	0.54	100	0	0	56160	100	53150	94.64	18.06	186
1000	0	0.08	0	17.16	0.36	0	0.55	100	0	0	55600	99	52800	94.01	16.8	200
1000.01	0.07	0.19	0	18.48	0.38	0	0.78	100	0	0	53130	94.6	50050	89.12	18.48	182
1000.01	0	0.18	0	19.09	0.83	0.02	0.62	100	0	0	52760	93.94	49690	88.47	18.42	182
1000.01	0.07	0.24	0	19.33	1	0	0.55	100	0	0	50040	89.1	46900	83.51	18.84	178
1000.01	0	0.3	0	18.44	0.72	0	0.54	100	0	0	48150	85.73	45010	80.14	18.84	178
1000.01	0	0.3	0	16.75	0.33	0	0.55	100	0	0	44920	79.98	41750	74.34	19.02	177
1000.01	0.03	0.21	0	18.12	0.57	0	0.59	100	0	0					18.35	183.29

F12

CPU1			CPU2			HDD					BAT begin		BAT end		Drain	BAT life
Tmr	Irq	Load %	Tmr	Irq	Load %	Rd	Wr	Act	StnBy	Slp	[mWh]	[%]	[mWh]	[%]	[W]	[min]
17.19	9.21	0.27	17.41	17.4	0.4	0	0.14	54.55	45.45	0	56160	100	53900	95.97	13.56	248
16.69	9.62	0.26	16.63	19.42	0.34	0	0.14	54.55	45.45	0	52880	94.15	50460	89.85	14.52	232
45.55	15.01	0.67	46.43	22.65	0.57	4.51	1.02	90.91	9.09	0	52240	93.01	49640	88.39	15.6	216
13.84	6.49	0.15	14.96	15.36	0.33	0	0.18	54.55	45.45	0	49600	88.31	47120	83.9	14.88	226
16.6	9.02	0.28	16.19	16.11	0.32	0	0.12	36.36	63.64	0	47810	85.13	45390	80.82	14.52	232
13.79	6.65	0.16	15.19	14.77	0.34	0	0.14	36.36	63.64	0	47100	83.86	44610	79.43	14.94	225
17.76	9.75	0.32	17.67	15.94	0.39	0.02	0.34	54.55	45.45	0	44560	79.34	42080	74.92	14.88	226
20.2	9.39	0.3	20.64	17.38	0.38	0.65	0.3	54.55	45.45	0					14.7	229.29

F12 tuned

CPU1			CPU2			HDD					BAT begin		BAT end		Drain	BAT life
Tmr	Irq	Load %	Tmr	Irq	Load %	Rd	Wr	Act	StnBy	Slp	[mWh]	[%]	[mWh]	[%]	[W]	[min]
20.04	9.52	0.33	19.81	13.96	0.37	0	0.18	63.64	36.36	0	54320	96.72	51760	92.16	15.36	219
16.59	6.92	0.26	17.3	10.49	0.35	0	0.34	81.82	18.18	0	51750	92.14	49090	87.41	15.96	211
16.64	6.75	0.27	16.5	12.1	0.31	0	0.16	72.73	27.27	0	49040	87.32	46400	82.62	15.84	212
16.52	7.11	0.26	17.07	11.98	0.39	0	0.18	72.73	27.27	0	46380	82.58	43750	77.9	15.78	213
17.45	7.58	0.28	17.67	12.13	0.36	0	0.22	72.73	27.27	0					15.74	213.75

Office workload

RHEL 5

CPU1			CPU2			HDD					BAT begin		BAT end		Drain	BAT life
Tmr	Irq	Load %	Tmr	Irq	Load %	Rd	Wr	Act	StnBy	Slp	[mWh]	[%]	[mWh]	[%]	[W]	[min]
999.81	0.1	2.97	0	43.3	4.28	1.08	4.55	100	0	0	56160	100	45730	81.42	17.37	194
999.79	0.1	3.22	0	43.3	4.52	3.46	5.23	100	0	0	54140	96.4	42220	75.17	19.85	169
1000.2	0.1	3.41	0	47.98	4.28	4.83	5.13	100	0	0	45180	80.44	32230	57.38	21.57	156
1000.21	0.1	3.25	0	41.98	4.23	0	4.49	100	0	0	42210	75.16	29880	53.2	20.54	164
1000.21	0.1	3.25	0	43.02	4.2	0	7.17	100	0	0	30350	54.04	17850	31.78	20.82	161
1000.21	0.1	3.49	0	40.78	3.77	0	4.43	100	0	0	29870	53.18	17240	30.69	21.04	160
1000.07	0.1	3.27	0	43.39	4.21	1.56	5.17	100	0	0					20.2	167.33

Fedora 12

CPU1			CPU2			HDD					BAT begin		BAT end		Drain	BAT life
Tmr	Irq	Load %	Tmr	Irq	Load %	Rd	Wr	Act	StnBy	Slp	[mWh]	[%]	[mWh]	[%]	[W]	[min]
243.54	32.55	9.29	235.04	60.62	7.41	2.43	1.21	94.59	5.41	0	54950	97.84	44850	79.86	16.82	200
236.49	32.64	8.83	230.32	58.44	7.42	1.62	1.15	92.6	7.4	0	54040	96.22	43890	78.15	16.9	199
222.65	32.83	7.49	228.47	59.41	8.08	0	1.1	93.25	6.75	0	44830	79.82	34400	61.25	17.38	193
226.22	29.28	8.37	217.43	60.51	6.89	0	1.12	89.92	10.08	0	43850	78.08	33210	59.13	17.73	190
223.15	32.39	7.9	224.69	55.19	7.84	0	1.12	92	8	0	34380	61.21	23710	42.21	17.78	189
231.07	28.42	8.45	225.75	57.72	7.46	0	1.05	86.41	13.59	0	33190	59.09	22430	39.93	17.93	187
230.52	31.35	8.39	226.95	58.65	7.52	0.68	1.13	91.46	8.54	0					17.42	193

Fedora 12 tuned

CPU1			CPU2			HDD					BAT begin		BAT end		Drain	BAT life
Tmr	Irq	Load %	Tmr	Irq	Load %	Rd	Wr	Act	StnBy	Slp	[mWh]	[%]	[mWh]	[%]	[W]	[min]
237.85	32.17	8.73	233.21	58.43	7.47	1.64	1.12	100	0	0	53250	94.81	43800	77.99	15.74	214
236.82	30.78	8.5	234.68	58.91	7.76	0	1.1	99.72	0.28	0	43780	77.95	34010	60.55	16.28	207
224.49	29.24	8.41	216.69	56	6.62	0	1.03	100	0	0	33990	60.52	23950	42.64	16.73	201
235.12	30.28	8.44	233.31	57.56	7.75	0	1.08	99.91	0.09	0	23930	42.61	13790	24.55	16.89	199
233.57	30.62	8.52	229.47	57.73	7.4	0.41	1.08	99.91	0.09	0					16.41	205.25

Reader workload

RHEL 5

Timer	Irq	Load	Irq	Load	Rd	Wr	Act	B-Cap	Chrg %	E-Cap	Chrg %	Drain	Bat life
997.43	0.24	10.73	63.84	11.78	9.47	11.62	100	56160	100	55540	98.89	19.24	175
998.06	0.16	5.68	46.37	9.59	0	9.01	100	55540	98.89	54950	97.84	21.03	160
998.17	0.19	6.79	45.98	7.59	0	9.64	100	54940	97.82	54360	96.79	20.88	161
1003.51	0.2	7.38	61.37	11.12	9.66	10.17	100	52820	94.05	52200	92.94	20.86	161
1004.98	0.2	8.1	48.38	7.02	0	8.29	100	52200	92.94	51580	91.84	22.32	150
997.03	0.21	7.86	48.06	6.76	0	8.28	100	51580	91.84	50990	90.79	21.24	158
999.86	0.2	7.76	52.33	8.98	3.19	9.5	100					20.93	160.83

Fedora 12

Timer	Irq	Load	Timer	Irq	Load	Rd	Wr	Act	B-Cap	Chrg %	E-Cap	Chrg %	Drain	Bat life
301.19	65.69	13.45	303.94	72.75	13.88	0.03	3.16	100	56080	99.85	55490	98.8	20.23	166
310.11	42.88	14.09	291.02	73.3	10.86	0	2.95	100	55470	98.77	54910	97.77	19.38	173
325.22	43.5	12.51	338.85	80.57	15.15	0.01	3.74	100	54890	97.73	54320	96.72	19.92	169
312.94	43.51	14.47	306.45	66.66	13.48	0	3.39	100	27500	48.96	26830	47.77	22.97	146
280.32	45.93	9.69	310.83	75.95	15.23	0	3.33	100	26780	47.68	26110	46.49	23.19	145
288.66	41.61	10.36	309.44	69.88	14.23	0	2.81	100	26080	46.43	25410	45.24	23.19	145
303.07	47.19	12.43	310.09	73.19	13.81	0.01	3.23	100					21.48	157.33

Fedora 12 tuned

Timer	Irq	Load	Timer	Irq	Load	Rd	Wr	Act	B-Cap	Chrg %	E-Cap	Chrg %	Drain	Bat life
276.68	43.67	12.8	272.88	63.95	11.73	0	1.97	100	51940	92.48	51360	91.45	20.47	164
305.3	40.93	12.59	318.8	76.05	15.17	0	2.24	100	51340	91.41	50760	90.38	20.47	164
273.4	35.17	11.62	282.98	64.34	12.75	0.01	2.21	100	50730	90.33	50160	89.31	20.12	167
285.13	39.92	12.34	291.55	68.11	13.22	0	2.14	100					20.35	165

Power consumption and HDD activity in charts

Conclusion

Fedora 12 is more power saving against RHEL 5 but it's not valid in all cases. The results illuminate dependency of power saving on used application. This conclusion will be investigated deeper in the future (e.g. test using another browser).
The next finding shows dependency of power consumption on charging rate. There is currently no clear explanation for this effect.
The data of CPU displays different ways in using two cores CPUs.
Tuned is able to increase power saving but not in all cases.

Wifi Power consumption

The test aimed at wifi power consumption. BLTK have been used to measure raw power consumption of connected wifi but without real data transmission. The laptop described below is installed with Fedora 11.

Hardware

LENOVO ThinkPad T61
* CPU Intel Core2 Duo CPU T7100 1.8 GHz
* Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller
* LCD 14" 1440x900x24
* 2 GB of memory
* HDD Hitachi 100 GB
* Battery designed capacity 56.16 Wh / usable capacity 40.96 Wh

Test description

The test was done using BLTK and its Office workload. The were used three use cases

wifi on - the laptop was near to the AP. Signal strength almost 100%.
wifi of
wifi on - the laptop was on another floor as the AP. Signal strength ~ 50%.

The office workload has been repeated four times:

bltk -O -n 4

Measurement was done three times for all use cases.

Results

Wifi strength [%]	Power Drain [W]	Bat-life [min]
100	17.76	189
100	17.83	188
	17.795	188.5

Wifi strength [%]	Power Drain [W]	Bat-life [min]
0	16.64	202
0	16.69	201
	16.665	201.5

Wifi strength [%]	Power Drain [W]	Bat-life [min]
~50	17.76	189
~50	17.76	189
	17.76	189

Conclusion

Wifi of tested laptop consumes against 1.1 W independent on signal strength when the laptop is connected but doesn't transmit any data. Due to battery state (usable aprox. 3/4 of designed capacity) switching wifi off can increase battery life about 9 minutes. This test should be extended about testing when the data is transmitted.

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SIGs/PowerManagement/RHEL5xF12comparison

Contents

RHEL 5 x Fedora 12

Used Hardware and OS

Test description

Result tables and charts

Idle workload

Office workload

Reader workload

Power consumption and HDD activity in charts

Conclusion

Wifi Power consumption

Hardware

Test description

Results

Conclusion