[Galaxy S I9000 General] distortedloop:
Voodoo battery life test GPL vs Stock kernel

Well, I have to admit that I was surprised at the results of my battery life comparison of JM8-voodoo vs GPL-voodoo! I honestly didn't expect the results I got, you may recall my only argument prior to testing was that GPL-voodoo wasn't inherently bad on battery life, not that it was better than JM8. Well, I was wrong, turns out that on my phone GPL-voodoo is easier on the battery than JM8! Amazing.

Okay, the testing wasn't anything extensive, but here's what I did. I installed Battery Graph from the Market on the phone then proceeded to test as follows:

I charged the battery to 100%, then booted recovery and installed the JM8-voodoo kernel on my already voodooed phone. When the phone finished booting, I opened several programs just to get things running (Foursquare, BeyondPod, Maps, Camera, Gallery, Watchdog, Gmail, Voice, Touiteur, then Battery Graph). I have WiFi, Bluetooth, GPS, Sync all on. I have multiple widgets running on the desktop (Google Finance, Weatherbug, PowerWidget). Gmail is running pull, and Touteur is running pull every 10 minutes, Google Finance every 30.

I then unplugged the phone and let it sit idle for an hour in a strong 3G signal area. After the hour, I woke the phone, played with battery graph for a few minutes, took some screen shots, saved the battery graph information. Time spent messing around after the hour of sleep was 7 minutes.

Next step was charge the battery to 100%, then boot recovery and reinstall my GPL-voodoo kernel and repeat the process exactly as above.

As a sort of control, I ran the same test on my Nexus One (with Kang-o-Rama version of Cyanogen Froyo & an OC/UV kernel).

Battery Graph was set to poll and log results every minute, this is an artificial increase on battery drain, but also keeps some routine activity going which I think helps the test.

The results:

JM8-voodoo battery drain was 3% while sleeping and an additional 2% while taking screen captures, etc.

GPL-voodoo battery drain was 2% while sleeping and an additional 1% while taking screen captures, etc.

Nexus One battery drain was 2% while sleeping over an hour period, 7% over a three hour period.

GPL-voodoo used significantly less battery in the 1:07 of testing on the two different runs.

Obviously this isn't thorough testing, but it's a start, and it reinforces my beliefs that GPL-voodoo is not in and of itself a battery hog as certain people try to imply. It also validates my perception that battery drain on my SGS with voodoo seemed about the same as on my other Android phones. A more thorough test would have to include actually using the phone for everyday tasks. Such testing might show some flaw in one kernel or the other; but such a test would be more difficult to replicate. I invite someone else to do it.

If GPL-voodoo is causing you battery issues, and you're on JM8 or JM7, there actually is a known RARE issue of some runaway activities, but no other firmwares have been reported as a problem.

Here are the actual minute by minute outputs from the Battery Graph:

sample_date	sample_date_in_seconds	battery_level
JM8-voodoo results
2010 Oct 05 13:09:31	1286309371	100
2010 Oct 05 13:10:32	1286309432	100
2010 Oct 05 13:11:32	1286309492	100
2010 Oct 05 13:12:33	1286309553	99
2010 Oct 05 13:13:32	1286309612	99
2010 Oct 05 13:14:32	1286309672	99
2010 Oct 05 13:15:32	1286309732	99
2010 Oct 05 13:16:32	1286309792	99
2010 Oct 05 13:17:32	1286309852	99
2010 Oct 05 13:18:33	1286309913	99
2010 Oct 05 13:19:32	1286309972	99
2010 Oct 05 13:20:33	1286310033	99
2010 Oct 05 13:21:32	1286310092	99
2010 Oct 05 13:22:32	1286310152	99
2010 Oct 05 13:23:32	1286310212	99
2010 Oct 05 13:24:32	1286310272	99
2010 Oct 05 13:25:33	1286310333	99
2010 Oct 05 13:26:32	1286310392	99
2010 Oct 05 13:27:32	1286310452	99
2010 Oct 05 13:28:32	1286310512	99
2010 Oct 05 13:29:32	1286310572	99
2010 Oct 05 13:30:32	1286310632	99
2010 Oct 05 13:31:32	1286310692	98
2010 Oct 05 13:32:32	1286310752	98
2010 Oct 05 13:33:32	1286310812	98
2010 Oct 05 13:34:32	1286310872	98
2010 Oct 05 13:35:32	1286310932	98
2010 Oct 05 13:36:32	1286310992	98
2010 Oct 05 13:37:33	1286311053	98
2010 Oct 05 13:38:33	1286311113	98
2010 Oct 05 13:39:32	1286311172	98
2010 Oct 05 13:40:32	1286311232	98
2010 Oct 05 13:41:32	1286311292	98
2010 Oct 05 13:42:32	1286311352	98
2010 Oct 05 13:43:32	1286311412	98
2010 Oct 05 13:44:33	1286311473	98
2010 Oct 05 13:45:33	1286311533	98
2010 Oct 05 13:46:34	1286311594	98
2010 Oct 05 13:47:33	1286311653	98
2010 Oct 05 13:48:33	1286311713	98
2010 Oct 05 13:49:33	1286311773	98
2010 Oct 05 13:50:33	1286311833	98
2010 Oct 05 13:51:32	1286311892	98
2010 Oct 05 13:52:32	1286311952	98
2010 Oct 05 13:53:32	1286312012	98
2010 Oct 05 13:54:33	1286312073	98
2010 Oct 05 13:55:33	1286312133	98
2010 Oct 05 13:56:33	1286312193	98
2010 Oct 05 13:57:32	1286312252	98
2010 Oct 05 13:58:33	1286312313	98
2010 Oct 05 13:59:32	1286312372	97
2010 Oct 05 14:00:33	1286312433	97
2010 Oct 05 14:01:33	1286312493	97
2010 Oct 05 14:02:32	1286312552	97
2010 Oct 05 14:03:32	1286312612	97
2010 Oct 05 14:04:33	1286312673	97
2010 Oct 05 14:05:33	1286312733	97
2010 Oct 05 14:06:32	1286312792	97
2010 Oct 05 14:07:33	1286312853	97
2010 Oct 05 14:08:33	1286312913	97
2010 Oct 05 14:09:33	1286312973	97
2010 Oct 05 14:10:33	1286313033	97
2010 Oct 05 14:11:33	1286313093	97
2010 Oct 05 14:12:34	1286313154	96
2010 Oct 05 14:13:35	1286313215	96
2010 Oct 05 14:14:38	1286313278	96
2010 Oct 05 14:15:38	1286313338	95
2010 Oct 05 14:16:38	1286313398	95
GPL Voodoo results
2010 Oct 05 14:58:18	1286315898	100
2010 Oct 05 14:59:19	1286315959	100
2010 Oct 05 15:00:18	1286316018	100
2010 Oct 05 15:01:19	1286316079	100
2010 Oct 05 15:02:18	1286316138	100
2010 Oct 05 15:03:19	1286316199	100
2010 Oct 05 15:04:19	1286316259	100
2010 Oct 05 15:05:18	1286316318	100
2010 Oct 05 15:06:19	1286316379	100
2010 Oct 05 15:07:19	1286316439	100
2010 Oct 05 15:08:19	1286316499	100
2010 Oct 05 15:09:18	1286316558	100
2010 Oct 05 15:10:19	1286316619	100
2010 Oct 05 15:11:18	1286316678	100
2010 Oct 05 15:12:19	1286316739	100
2010 Oct 05 15:13:19	1286316799	100
2010 Oct 05 15:14:19	1286316859	100
2010 Oct 05 15:15:18	1286316918	100
2010 Oct 05 15:16:18	1286316978	100
2010 Oct 05 15:17:19	1286317039	100
2010 Oct 05 15:18:19	1286317099	100
2010 Oct 05 15:19:18	1286317158	100
2010 Oct 05 15:20:18	1286317218	100
2010 Oct 05 15:21:19	1286317279	100
2010 Oct 05 15:22:18	1286317338	100
2010 Oct 05 15:23:20	1286317400	100
2010 Oct 05 15:24:19	1286317459	100
2010 Oct 05 15:25:20	1286317520	100
2010 Oct 05 15:26:18	1286317578	100
2010 Oct 05 15:27:19	1286317639	100
2010 Oct 05 15:28:19	1286317699	100
2010 Oct 05 15:29:19	1286317759	100
2010 Oct 05 15:30:18	1286317818	100
2010 Oct 05 15:31:19	1286317879	100
2010 Oct 05 15:32:18	1286317938	100
2010 Oct 05 15:33:19	1286317999	100
2010 Oct 05 15:34:19	1286318059	100
2010 Oct 05 15:35:18	1286318118	100
2010 Oct 05 15:36:18	1286318178	100
2010 Oct 05 15:37:20	1286318240	100
2010 Oct 05 15:38:18	1286318298	100
2010 Oct 05 15:39:18	1286318358	100
2010 Oct 05 15:40:19	1286318419	100
2010 Oct 05 15:41:19	1286318479	100
2010 Oct 05 15:42:19	1286318539	100
2010 Oct 05 15:43:19	1286318599	100
2010 Oct 05 15:44:18	1286318658	100
2010 Oct 05 15:45:18	1286318718	100
2010 Oct 05 15:46:18	1286318778	100
2010 Oct 05 15:47:19	1286318839	100
2010 Oct 05 15:48:19	1286318899	100
2010 Oct 05 15:49:18	1286318958	100
2010 Oct 05 15:50:18	1286319018	100
2010 Oct 05 15:51:19	1286319079	99
2010 Oct 05 15:52:18	1286319138	99
2010 Oct 05 15:53:19	1286319199	99
2010 Oct 05 15:54:19	1286319259	99
2010 Oct 05 15:55:19	1286319319	99
2010 Oct 05 15:56:19	1286319379	99
2010 Oct 05 15:57:20	1286319440	99
2010 Oct 05 15:58:21	1286319501	98
2010 Oct 05 15:59:21	1286319561	98
2010 Oct 05 16:00:21	1286319621	98
2010 Oct 05 16:01:21	1286319681	98
2010 Oct 05 16:02:22	1286319742	98
2010 Oct 05 16:03:22	1286319802	98
2010 Oct 05 16:04:22	1286319862	98
2010 Oct 05 16:05:21	1286319921	97