Risk in using multiboot
 

Guys I'm really slow in this development of n900
But is it true that it is a risk in using mulitboot for NITDroid?
What i heard is that there are limits to number of times NAND memory can be flashed.
So every single boot into NITDroid would be a flash..
So maybe a month 30 to 50 times of flashing?

And also is uboot using another method instead of flashing kernels?

TQ

Re: Risk in using multiboot
 

No, multiboot is not flashing.

The thing with limited writes to NAND memory is that every NAND block can only be flashed a number of times. WIth normal usage and wear-levelling done by the filesystem or at the controller-level, NAND still lasts longer than a harddisk would do on average.
So, don't worry. :)

Re: Risk in using multiboot
 

Howzit Pang,

My very first post on this site. Thanks for informing about the flash. It will be a lot more than 30-50 times. EEPROMs (if it be) wil last WAY lot longer. Imagine how many times sectors gets written to before it 'naturally' becomes bad. No fear on this .... yet....bwaahaa! Reminds me of Dr Evil.

I'm seriously intrigued by this mobile computing device I bought - was waiting for it since March. The cellphone world in South Africa sucks. I saw the E7 and it will only arrive middle next year.

Anyway, I'm a UNIX guys - live UNIX completely...work&play. Never did any programming ever - except shell scripting and a tad bit of perl. Would love to start. So much info, so little time. Where to start? What to grasp firstly? ....and how do I su to root user on the device, so I can actually list all data and pipe it out to file? "user" user is super-restricted...

Sorry, lots of questions. Maybe you can help? Thanks.

Re: Risk in using multiboot
 

OK thanks alot..
I seriously needed those type of infos.
So do you have any info on how nitdroid boot into n900?
Any specific method? or just like how maemo boot into n900

Re: Risk in using multiboot
 

You have to install rootsh in app manager
From there you get to use sudo gainroot in xterminal.
Is that what youre looking for?

Re: Risk in using multiboot
 

Thus far, nope. I just got the N900 and let it morph into an "extension of my personality" so to speak. I had a N6210 for 4 years. Was never big on devices, only UNIX.
I really really enjoy this device. I know little about the dual boot thing yet. Need to get it integrated into WiFi and USB @ work, so I can do my system admin work via N900. I got the terminal going. The thing uses my cell phone service provider for everything and it irritates the hell out of me. I need to switch from paying for everything to have data route via my LAN @ home & work.

As soon as I have info, I will share it for sure. You DO know we own everything ANYWAY! [ :-) ] No point in keeping to myself.

Re: Risk in using multiboot
 

So did u get the "root" user?

Re: Risk in using multiboot
 

Yeah,, i think.
I have an xterm that I got with the N900. What does NOT work is:
su - root
sudo su - root
sudo su - etc - tried lots of different.

It asks for a password, and just hitting return goes back to prompt, but 'whoami' tell me I'm user. Other commands have me with error output pointing to the ID 'user' not having enough permission. I believe this O/S was built to not have a cowboy go screw it up, so they made sure no-one 'needs' root for anything... Maemo obviously boots off a "read-only" source that can be altered by something other than a live O/S, like flashing etc.

Re: Risk in using multiboot
 

Last I checked, the N900's NAND doesn't have wear level. The eMMC (where MyDocs, etc, goes) does, but I've read people more knowledgeable than myself on here say that the NAND doesn't wear-level.

More over: Everyone on here who's ever said anything about multiboot other than the second poster has said that multiboot does flash the kernel.

When you boot into multiboot and select the OS to boot, it flashes that kernel image in place of whatever's on the NAND, and reboots. So, upon reboot, you're loading with the new kernel.

uboot on the other hand does not need to flash, because uboot can load a kernel image that's configured properly from ANYWHERE on the device. It's less intuitive and not exactly newb-friendly to make it work, but it's definitely better.

However, keep in mind that modern flash chips have like hundreds of thousands of erasable 'layers'. So you've got hundreds-of-thousands of writes, even without wear-leveling. If you boot into different OSs, say, ten times a day, that's still over 10 years before you kill your chip. So you shouldn't worry about it TOO much.

I always recommend uboot because I think it's more versatile and in the long run it will be better to have people switch to that, especially if a N900 newb-friendly version with easy commands like "run nitdroid" and "run meego" is made available. Which I suspect there will be, and soon.

Oh, the root access stuff - with rootsh downloaded, just typing "sudo gainroot" or "root" will elevate you to the root user, without asking for password. "su", I think, doesn't work the same way on the N900, if it exists at all. All other "sudo [something]"s ask me for a password, which is not the same password and my normal root one, or my user one, so *shrug*. I only once figured out how to set that password, and that was two reflashes ago and I don't bother, because I usually just use sudo gainroot anyway.

Re: Risk in using multiboot
 

Yes, in fact it flashes a kernel to the kernel area. That I haven't nuked my own N900 kernel area or N8x0 yet speaks to the fact it's difficult to kill a NAND :)