How to upgrade the internal memory by extending the root filesystem to a memory card
 

I found out how you can upgrade the Nokia 770 Internet Tablet's internal memory by extending the root filesystem to a memory card. My step-by-step guide with detailed instructions has been posted on the Maemo Wiki. Following the steps, one can expand the unit's memory, make it persist even through flashing, and protect the internal flash memory's durability all at the same time. All power users are welcome to check it out and see if it helps them to get even more out of our favorite Linux device. Here's the link: http://maemo.org/maemowiki/ExtendedRootFilesystem

Wow! Nice Wiki page :)

Just a couple of (probably stupid) questions. What happens when you plug the USB cable into the 770 after you've done this hack? Does it affect how the device appears to the host PC? And I assume just like when running swap on a MMC plugging and unplugging the MMC while the device is on would be bad? That might be worth mentioning in the Wiki if so. Can you combine this with the swap space on MMC hack also?

Great guide, now i'll just have to get myself a 1gb card and give it a try. :)

Simon, I think the first paragraph in the "First Step - Preparing the memory card:" section covers the usb connection issue. Not sure which method you used for creating the swap, but i used the one that has you create another partition and i can connect the usb without any problem. The device appears the same on my pc, just shows as being something like 48mb instead of 64.

Oh yes, it does mention the first partition works the same as normal. I missed that bit sorry.

I haven't actually played with swap partitions yet. I was going to try that on the 64MB card first. I haven't had a chance to play with it on my Linux box to figure out how to partition it yet.

What does this do to the device's internal storage? Does it just sit unused?

Hey there - thanks for the nice comments! :)

As has been pointed out, the normal functioning of the memory card won't be affected as we're using an independent partition, so there's no problem with unmounting. It shouldn't be removed from the device, of course, unless you revert the changes first. With the script I provided, this can be done painlessly.

And yes, it can be combined with the swap. I recommend a swap file instead of a swap partion since we already created a new partition. While you could create a third one, it's probably better to simply create a swap file on the new partition, with a big memory card you'll have more than enough space. Then you can always change its size by recreating the swap file, that's easier than repartitioning and resizing a partition, so you get more flexibility. I'll add that information to the Wiki page soon...

The internal memory is still used for everything not swapped out onto the memory card. While you could move pretty much everything onto the card, I only use it for home directories and configuration files. If everything were to be put on the memory card, you'd lose the ability to instantly restore the device to your customized working state after reflashing, since then you'd have to update the files on the memory card as well. It would be fun to investigate a three-partition-setup: The first partition as the normal memory card, the second partition for home directories and configuration files, and a third one for all of the remaining stuff. So you see, there's still a lot of room for further improvement!

I feel foolish asking this question but i'd love to get a step by step guide to this - lol yes even more detailed than wolfram - i get confused at the first step.

Well, actually the first step is the most difficult one, steps two and three are handled by the script. But that's what the forums are there for, to ask for help and discuss solutions. If you can describe your situation in more detail, I or someone else can try to help you better.

How to create and use a swap file together with an Extended Root Filesystem
 

I just updated the Extended Root Filesystem HOWTO with information on how to create and use a swap file together with an Extended Root Filesystem.

Since it's a file on the new partition, it won't be unmounted when the device is connected to a computer by USB. And as a regular file, it can be resized easily. It's a compromise between creating a swapfile and using a new partition for swap - which combines the advantages of both (and much more).

What's best about my way of (de)activating swap is that this works independently of the actual swap file or partition. The startup, reboot and shutdown scripts will work the same no matter if there's swap available or not. To add or remove a swap file or partition, simply modify /etc/fstab (after manually deactivating swap with swapoff -a), without having to touch the scripts again. Even if you decide against swap, it's enough to delete or comment out the line(s) in /etc/fstab, the scripts will keep working. I'd actually like Nokia to include something like that in their own system scripts with a future version of the 770's OS.

I hope you find it useful and welcome further discussion here.

How big?
 

OK -- I bought a 1 GB mmc card. I have root access. I'm about to boot up from a LiveCD and repartition and reformat the brandnew card.

What size should I make the second partition?

I will be putting a swap file on there. I'd like to be able to put a lot of unnecessary applications on my 770 :D -- well, you know what I mean: lots of applications that I want to check out but won't use regularly, and apps I want as insurance (so that I can work on some file if I ever have to, for my job and such -- something like the gnumeric spreadsheet app). What size do you think should be big enough, without being too big and squandering space?

Your guidance here would be most appreciated.

Thanks,

Roger