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Shaggy · 04-09-2009, 09:17 AM

There's a lot of mixing of terminology out there, and some confusion. If you're interested in a lot of the details there are threads over on the iRex forum discussing it.

In short though, they are planning on two power saving modes.

1) Suspend-to-RAM is basically a way of quickly putting the device into a power conservation mode with an equally quick recovery. Originally they estimated that this mode would allow the power consumption to slow down enough to last for 24 hours, but most experience shows it's around 10 - 14 hours. They are making tweaks to this mode to try and improve the power savings in a firmware that is currently being tested. No word yet on how much (if any) improvements to the sleep time they have made.

2) Suspend-to-Flash is a way of putting the device into an even "deeper sleep". Basically a snapshot of the current state of the machine is written to flash memory and the entire device is essentially suspended. Recovery from this mode is slower (they've said around 10 seconds), but it will (theoretically) be able to stay in this mode for "weeks". How that turns out in reality is not yet known. Currently they have said that they plan on including this in a future update, but I have not heard any additional information about when that will be.

The terms "sleep", "suspend", etc seem to be used interchangeably for the two modes, depending on who you ask, so it gets a little confusing.

As far as the technical differences, RAM is quicker but you still need to maintain power to the memory in order to keep the data that has been written there. Flash is slower, but it's essentially "permanent", so you can suspend just about everything except the buttons and stylus (so that it'll wake again). Suspend to flash basically turns it into an "always on" device rather than have to shut it down and boot it up every time you want to use it. So if you're reading during the day and pause for 10 minutes, that's a suspend to RAM. If you set it down and want to continue reading with it tomorrow, that's a suspend to flash.

04-09-2009, 09:17 AM	#22
Shaggy Wizard Posts: 4,293 Karma: 529619 Join Date: May 2007 Device: iRex iLiad, DR800SG	There's a lot of mixing of terminology out there, and some confusion. If you're interested in a lot of the details there are threads over on the iRex forum discussing it. In short though, they are planning on two power saving modes. 1) Suspend-to-RAM is basically a way of quickly putting the device into a power conservation mode with an equally quick recovery. Originally they estimated that this mode would allow the power consumption to slow down enough to last for 24 hours, but most experience shows it's around 10 - 14 hours. They are making tweaks to this mode to try and improve the power savings in a firmware that is currently being tested. No word yet on how much (if any) improvements to the sleep time they have made. 2) Suspend-to-Flash is a way of putting the device into an even "deeper sleep". Basically a snapshot of the current state of the machine is written to flash memory and the entire device is essentially suspended. Recovery from this mode is slower (they've said around 10 seconds), but it will (theoretically) be able to stay in this mode for "weeks". How that turns out in reality is not yet known. Currently they have said that they plan on including this in a future update, but I have not heard any additional information about when that will be. The terms "sleep", "suspend", etc seem to be used interchangeably for the two modes, depending on who you ask, so it gets a little confusing. As far as the technical differences, RAM is quicker but you still need to maintain power to the memory in order to keep the data that has been written there. Flash is slower, but it's essentially "permanent", so you can suspend just about everything except the buttons and stylus (so that it'll wake again). Suspend to flash basically turns it into an "always on" device rather than have to shut it down and boot it up every time you want to use it. So if you're reading during the day and pause for 10 minutes, that's a suspend to RAM. If you set it down and want to continue reading with it tomorrow, that's a suspend to flash.