Trashed NAND


Given that we only have 512MB of NAND, would a utility be useful for folks that backs up the entire of the NAND to a compressed file which, if present on the left SD card could be used to restore to a known state? If people don't want to devote a few hundred megs of SD space to it they can opt not to, but given the size of SD cards these days it might be a useful option. If this archive could be created at any time by the user, it would be very good indeed - it would be pointless to have it as an option in the OS installer, but tucked away in the system menu would be more useful.

Yes, that's what I thought a few days ago as well. It would be enough to save the users home directory, username, overclocking config, etc. and if the First boot wizard finds that file, asking first if you want to do an automatic setup.
 
It's just an inconvenience; nothing of value was lost.


It's odd that the Pandora was completely unable to boot - all I could do was start again at the boot menu, and set up sz5a from SD Card again :(


What is galling is that I'll have to go through the whole first-boot setup again, then set up the desktop as I like it, removing the icons from the taskbar/panel and setting the theme and compositing options etc.


Which leads me onto another question...


Given that we only have 512MB of NAND, would a utility be useful for folks that backs up the entire of the NAND to a compressed file which, if present on the left SD card could be used to restore to a known state? If people don't want to devote a few hundred megs of SD space to it they can opt not to, but given the size of SD cards these days it might be a useful option. If this archive could be created at any time by the user, it would be very good indeed - it would be pointless to have it as an option in the OS installer, but tucked away in the system menu would be more useful.


Then we'd just need the bootloader to be modified to use it...


Thoughts?


D.

Yes someone did a tool like this, but i don't remember who !!!
 
Last edited by a moderator:
Just checking that we need to be running the 3.2 Kernel to run Android. Booted with the old kernel but Android would not start, my guess is that this is normal and expected rather than some individual problem.


Thought I'd better check as I'd not seen any mention that running the 3.2 Kernel was required to run Android.


@ Dunny : +1 for your idea of an optional complete backup of the Nand and a boot option to restore this backup. This could be useful if you need to reflash but don't net access.
 
@ Dunny : +1 for your idea of an optional complete backup of the Nand and a boot option to restore this backup. This could be useful if you need to reflash but don't net access.

+1 to this. I always have a copy of the latest beta hotfix thingy on SD1 anyway, just for this eventuality.


ED: Why not just back up the entire NAND? You could flag the backup with the OS version to prevent accidental overwrites when the user upgrades... Needs to be recognised by the bootloader menu - otherwise that defeats the purpose; you'd still have to go through all that rubbish about usernames and whatnot before you can get to a desktop!


D.
 
Last edited by a moderator:
I haven't normally installed enough to the NAND to care about backing it up. reflash to current hotfix, install timidy, Java and codec pack and I'm back to normal.
 
Last edited by a moderator:
Haha! Although the Pandora was totally trashed, when I finally got back to a desktop and launched Android again (glutton for punishment that I am), it launched and ran perfectly, including the market. How ironic :)


D.
 
anyway, a key combo to kill android would be very appreciated. Need for hard resets is quite common with the current approach.
 
anyway, a key combo to kill android would be very appreciated. Need for hard resets is quite common with the current approach.

This. I've downloaded Google maps from the market, fired it up and now my Panda is in an infinite(?) loop doing something to the left SD card - and has been for over an hour now. If I reboot, I stand to lose the SD card if not the NAND as well. If I just eject the SD card... well, that would be stupid. And of course, the entire Android OS is now unresponsive.


D.
 
Wait! This seems to happen to 256mbunits because of some issues. You can reduce those by using a big swapfile without zram.
 
Wait! This seems to happen to 256mbunits because of some issues. You can reduce those by using a big swapfile without zram.

Excellent! I just need a way out of this problem first ;-)


D.
 
We might (MIGHT!) have found the solution.


Apparently, ubifs default config changed with Kernel 2.6.39: They had crc_check enabled before - and now this was switched off.


According to their website, disabling CRC gives a bit speed improvement, but it might cause broken filesystems when something like a power loss happens.


So this could very well be our case here.


I'll prepare an updated firmware with all these fixes soon.
 
Wait! This seems to happen to 256mbunits because of some issues. You can reduce those by using a big swapfile without zram.

As someone who's had to reflash my 256MB Pandora quite a few times by now, how can you tell if zram is actually running? I've noticed that when flashing the Pandora, I always seem to get an error message about zram, think it's something about being anable to assign a directory?(I'm not 100% sure of the details TBH)
 
That's not an Android bug.


It's some bug still left in the new kernel 3.2, it can also happen when the unit freezes in the normal OS right now (happened 2 - 3 times for me already. Need to try to reproduce it while a BoB is connected to send logs to notaz).
Does deleting the META-INF file in the gingerbread folder not fix this?
 
That's not an Android bug.


It's some bug still left in the new kernel 3.2, it can also happen when the unit freezes in the normal OS right now (happened 2 - 3 times for me already. Need to try to reproduce it while a BoB is connected to send logs to notaz).
Does deleting the META-INF file in the gingerbread folder not fix this?

No - I deleted mine long before the crash. Android crashes a lot.


D.
 
hmm, I've deactivated zram and swapped to a 512 MB file today, regularly kill apps with advanced task killer and everything seems rather stable.


Anyway, I'd call it a rather frustrating endevour for now. The only graphically modern game I got to run by now (Assassins Creed) doesn't recognize game keyboard inputs :(
 
If you want to check, if zram is running, type free in a terminal after booting angstrom. You should see about 60mb swap there.
 
We might (MIGHT!) have found the solution.


Apparently, ubifs default config changed with Kernel 2.6.39: They had crc_check enabled before - and now this was switched off.


According to their website, disabling CRC gives a bit speed improvement, but it might cause broken filesystems when something like a power loss happens.


So this could very well be our case here.


I'll prepare an updated firmware with all these fixes soon.

In the meantime it seems that reflashing may not always be necessary when this happens. I recently dropped one of my units, and when I picked it up it had reset and was refusing to boot kernel 3.2, though it did successfully boot kernel 2.6.


An IRC conversation led to the suggestion of powering down and removing the battery for 10 mins. This actually worked and I was able to boot into kernel 3.2 again without a reflash.


- Neelix
 
Wait! This seems to happen to 256mbunits because of some issues. You can reduce those by using a big swapfile without zram.
Actually, there's no problem with zram and Android. You just have to make shure that zram has higher priority than any SD-backed swap you may add - otherwise you'll lose the memory to zram but it will never be used (happened to me). Zram swap seems to have prio 5, so additional swap needs to have a lower priority (swapon -p0 swapfile).
 
Back
Top