Thread: n800-s2ram ? What is this ?
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fanoush is offline fanoush
2008-07-22 , 07:52
Posts: 2,152 | Thanked: 1,490 times | Joined on Jan 2006 @ Czech Republic
#40
Originally Posted by igor View Post
I don't want to discourage experimentation, in fact it's really cool to see such projects, if nothing else because they promote knowledge of runtime embedded power management.

However I have a question: did anybody measure the increased battery lifetime with this mod?

If not, the first step would be to check how many days a specific unit (pair device-battery) lasts with the stock idle power saving and stock image, and then how long the same unit can live in idle with s2ram.

When i say idle, i really mean it, no usage at all, so this is probably for somebody with a spare / old unit.
I tested this three times on completely idle N810 with Chinook OS2008 FW and it lasted approx 30 days (29,30,31). I did a quick check once a week if the unit is still alive so it theory it could last a bit longer.

s2ram project is indeed cool but there are only some use cases where this is really useful.

1. you really want to save battery when somewhere in the desert with no electricity
2. you are running buggy software on the background which eats CPU


Since case 2 is quite frequent it really makes sense to have some sort of real device suspend. BTW, writing kernel thread that kicks watchdog (without waking up userspace) could be interesting (but dangerous).
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Last edited by fanoush; 2008-07-22 at 07:59.