Sleep vs power off - battery life

kiwipippa · 12-30-2010, 11:00 PM

Does anyone know what the kobo is actually doing when the device is in sleep mode rather than powered off? I recently upgraded my original kobo to 1.8.1 and disabled the auto power off function so my kobo only slept. It was so easy to pick it up and start reading again - but the down side was a massive reduction in battery life. I have changed it back so it now powers down automatically. I have my covers back so it's a good compromise as I don't want to charge all the time. Just interested in why "sleep" seems to consume more battery.

Psyke · 12-30-2010, 11:18 PM

it's more or less keeping the RAM active, so as not to have to load the entire OS or book you might happen to be reading back into it. When you turn the device off, it flushes the memory and records anything it needs to the flash storage unit (ie - bookmarks). I also believe that if the wireless is left on, it's also on in sleep mode, but not 100% sure on that one.

Another thing to keep in mind is if you have magazine/newspaper subscriptions; if the system is set to auto check for new content, it will wake itself up to do so, and then go back to sleep. I think it's only supposed to do it once a day though, unless it can't make a connection, then it checks once an hour (need confirmation on this...I usually keep it off since the bug was reported in october, even though it was since fixed).

kiwipippa · 12-31-2010, 12:33 AM

Thanks Psyke, a great explanation. I don't have the wifi version, but it will be the RAM activity causing the difference.

12-30-2010, 11:00 PM	#1
kiwipippa Fanatic Posts: 578 Karma: 613022 Join Date: Aug 2010 Location: New Zealand Device: kobo glo, kobo touch (dead), kindle touch, android phone	Sleep vs power off - battery life Does anyone know what the kobo is actually doing when the device is in sleep mode rather than powered off? I recently upgraded my original kobo to 1.8.1 and disabled the auto power off function so my kobo only slept. It was so easy to pick it up and start reading again - but the down side was a massive reduction in battery life. I have changed it back so it now powers down automatically. I have my covers back so it's a good compromise as I don't want to charge all the time. Just interested in why "sleep" seems to consume more battery.

12-30-2010, 11:18 PM	#2
Psyke Evangelist Posts: 482 Karma: 534340 Join Date: Oct 2010 Location: Ottawa/Canada Device: Kobo Wi-Fi - Kobo Touch - GNex - N7	it's more or less keeping the RAM active, so as not to have to load the entire OS or book you might happen to be reading back into it. When you turn the device off, it flushes the memory and records anything it needs to the flash storage unit (ie - bookmarks). I also believe that if the wireless is left on, it's also on in sleep mode, but not 100% sure on that one. Another thing to keep in mind is if you have magazine/newspaper subscriptions; if the system is set to auto check for new content, it will wake itself up to do so, and then go back to sleep. I think it's only supposed to do it once a day though, unless it can't make a connection, then it checks once an hour (need confirmation on this...I usually keep it off since the bug was reported in october, even though it was since fixed). Last edited by Psyke; 12-30-2010 at 11:21 PM.

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12-31-2010, 12:33 AM	#3
kiwipippa Fanatic Posts: 578 Karma: 613022 Join Date: Aug 2010 Location: New Zealand Device: kobo glo, kobo touch (dead), kindle touch, android phone	Thanks Psyke, a great explanation. I don't have the wifi version, but it will be the RAM activity causing the difference.

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