Use NAND as a recovery partition?


Grench

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The short of it - treat the NAND as a recovery partition.


OK - so I've been booting off of an SD card since 4 days after I got my Pandora. Works fine - maybe even better than the internal NAND since user profile space isn't an issue. Reading through some of the HF6 threads, the size of the NAND is a limiter to what we can include for drivers and software with the image.


Here is my idea:


1. Start requiring that anyone who owns a Pandora also own an SD card to put in the left slot and leave there for the OS to ride on. A 2GB card is $6 and a 32GB card is $42. Not exactly a high barrier for someone buying a $500 device.


2. Have the OS image place the basics to boot to command line and a single huge compressed file in the NAND containing the OS image (which can be BIGGER than the one we're using now). I'm not encouraging code bloat, but having a bit of breathing room in the OS load would be refreshing.


3. If you boot from the NAND, have it automatically ask the following:


-This process will erase any data on the card in the left slot and load the Pandora Operating System to it. Continue (Yes,No)?


-How much of the card in the left slot would you like to assign to the OS (1000KB minimum, 32000KB maximum)? <- query the card and put in the card's size as maximum.


-How much of the card in the left slot would you like to assign to an optional swap partition (0KB minimum, 4000KB maximum)?


-Do you prefer the remainder of this card to be formatted as a FAT32 or EXT2 partition?


Please plug this Pandora into the AC adapter and go find something else to do for the next 30 minutes or so while the OS installs.


4. Then the OS installs to the SD/SDHC/SDXC card in the left slot. If that card ever dies, drop in another one, boot from NAND and have it back up and running in 30 or so minutes.


I don't see any drawbacks to this. So... why not?
 

WizardStan

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Strictly booting off an SD card is disadvantageous to the average user. Once that SD card is mounted you can't unmount it. You can't remove it, can't put it into mass storage mode, there is no way to quickly and easily copy things onto it. Furthermore, it'll need to be formatted EXT which is not automatically compatible with Windows. The desire is to make the Pandora MORE friendly to Average Joe User; doing as you describe is a step away from that goal.
 

Prometheus

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I don't see any drawbacks to this. So... why not?
I do - this;

1. Start requiring that anyone who owns a Pandora also own an SD card to put in the left slot and leave there for the OS to ride on. A 2GB card is $6 and a 32GB card is $42. Not exactly a high barrier for someone buying a $500 device.
You may not do so, but myself (and likely a number of others), I actually use both slots for cards full of data (both 32GB, in my case), with no room on those cards for an OS as well. Requiring that we aren't allowed to use the NAND for an OS because those who can add more libraries and whatnot to their SD installs don't want us to use our setups as we see fit, doesn't strike me as a particularly good solution, somehow.
 

Caine

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Having the option to do this is great, forcing it onto all users...not so much.
 

darfgarf

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apart form what's already been said, the nand is faster than lots of sd cards too, booting off an sd card for serious use is just too slow


though keeping the nand for playing games, and an sd image for developing is a decent way to go
 

Grench

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A lot of the naysayer arguments seem to be coming from people who have never booted from the SD slot - or who assume that all SDHC memory is snail slow.

What would be the main advantage of all this?
No more space constraints. If the user wants to put a 100MB reference file on their desktop, no issues. Not that there is a need to, but you get the idea. More flexibility. The ability to house a more full OS image with nifty things already in it - or the ability for the user to add nifty things to it through non-PND downloads & installs.

Strictly booting off an SD card is disadvantageous to the average user. Once that SD card is mounted you can't unmount it. You can't remove it, can't put it into mass storage mode, there is no way to quickly and easily copy things onto it. Furthermore, it'll need to be formatted EXT which is not automatically compatible with Windows. The desire is to make the Pandora MORE friendly to Average Joe User; doing as you describe is a step away from that goal.
No disadvantage really.


You can't unmount the OS or the swap partitions.


You CAN unmount the additional data partition.


You CAN put the additional partition in mass storage mode.


You CAN quickly and easily copy things onto it.


The data partition (not OS not SWAP) could be formatted as EXT or FAT.


The only partition(s) that you would not be able to do the above with are the OS install partition (2 GB?) and an optional swap partition (1 GB?).


This card would not be removable while the OS is running. That much is true.


You could still power down the Pandora, pull the card, put it in a card reader and go to town on the ~30GB data partition.


Clearly the, "Average Joe" had great difficulty in understanding that the IBM PC booted to a BASIC interface and required the user to put in a disk before an OS could be installed.


This is -easier- in the end. The "Average Joe" knows that to use his camera, camcorder, etc... he needs to put a card in the slot.


Since the OS install to the card can be automated with default prompts, "Average Joe" won't really have much to do.

I don't see any drawbacks to this. So... why not?
I do - this;

1. Start requiring that anyone who owns a Pandora also own an SD card to put in the left slot and leave there for the OS to ride on. A 2GB card is $6 and a 32GB card is $42. Not exactly a high barrier for someone buying a $500 device.
You may not do so, but myself (and likely a number of others), I actually use both slots for cards full of data (both 32GB, in my case), with no room on those cards for an OS as well. Requiring that we aren't allowed to use the NAND for an OS because those who can add more libraries and whatnot to their SD installs don't want us to use our setups as we see fit, doesn't strike me as a particularly good solution, somehow.
You have 64GB of cards in the thing and don't have room to give 1GB to the OS? Really? I saw that 64GB SDXC cards are coming down in price - I saw one at $99 on Amazon the other day. If you're that jammed for space, get a bigger card. If you have two 128GB SDXC cards full in it... then maybe you'd need that extra 1-3GB that this solution would take away...

Having the option to do this is great, forcing it onto all users...not so much.
Which is worse? Requiring users to buy an SD card for a device that runs on SD cards OR compromising the ease of use of the OS and device because you just can't shoe horn in everything that should be there into the 512MB that you have to work with?

apart form what's already been said, the nand is faster than lots of sd cards too, booting off an sd card for serious use is just too slow


though keeping the nand for playing games, and an sd image for developing is a decent way to go

My rough timing (I don't have a watch so I counted it out - someone else could do it more accurately):


NAND boot 43 seconds.


SDHC boot 64 seconds.


I'm not using the fastest cards, but I have found them to be reliable. Patriot LX 32GB Class 10. Amazon shows them as $52 each.


Anyway, we're not talking faster by factors. The NAND is about 30% faster than the SDHC card for booting. General operation of one Vs the other - you won't notice after booting. I rarely boot the device more than once every few weeks.


I'm not saying this has to happen - but I do think it should be considered with an open mind. 'Different' is always easy to chastise. Every new idea is 'different' by definition. Sometimes a new idea turns out to be good. Sometimes anyway.


Oh - one more advantage. If there is an OS upgrade, the "Average Joe" simply downloads a PND file using his SD mounted OS. The PND opens the NAND - clears it - then writes in the new OS image. The user then reboots, waits 30 minutes and the OS on the SD card is updated/upgraded.
 
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WizardStan

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Ok, instead of arguing the "should we"s, I'm going to go straight to the "can we", save a lot of argument.


No, we can't.


The NAND is already formatted with a compressed file system. Everything that is stored on it effectively gets zipped up. If it is full, and you took a copy of it, zipped it up, and made that zip the only thing on it, the NAND would still be full. Almost, anyway, there's a little play for overhead and slightly inefficient compression to allow faster random access, but not as much as you're hoping for. If we have space constraints now, creating a compressed recovery partition is not going to give us a lot more space for additional features to be uncompressed to an SD card.
 

Prometheus

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You have 64GB of cards in the thing and don't have room to give 1GB to the OS? Really? I saw that 64GB SDXC cards are coming down in price - I saw one at $99 on Amazon the other day. If you're that jammed for space, get a bigger card. If you have two 128GB SDXC cards full in it... then maybe you'd need that extra 1-3GB that this solution would take away...
I don't have room to give up space on my cards for the OS, that's correct - the OS is on the device, and accordingly, I don't need to concern myself with keeping room for the OS on my cards, leaving me free to use those (and the others I've amassed over time, which I keep to hand, and which I switch between) as I find most useful.


I'm afraid I don't see $99 (or £61, in my local currency) as a particularly reasonable price to spend on something that I don't need, personally, especially when the way things currently are is much better for my own uses than the solution proposed by this thread. ;) Personally, I think that that's the beauty of the way things currently are - everyone can set things up as they wish to, and spend as much as they need to.


Now, don't get me wrong (or lump me as a "naysayer" and assume that I am assuming things), I do think this would be a good option to have - the more the merrier, and the more flexible things become. However, I think as a default, I personally feel that it would take a lot of the stock flexibility away from the system. Indeed, you may not believe this, but the requirement you suggest would have put me off of purchasing the Pandora, as it would have seemed to be too much hassle to me to have two SD Card slots but only actually be allowed to use one (I unmount and swap cards whilst still powered on, for example, or unmount and add things to the one in the left slot, which is filled with my most-changing data - that wouldn't be possible with this).


EDIT: You know, I just realised, if this was in place early on, when the earliest encounters with the problems with certain SD Cards came about, that would have been disastrous. :blink:
 
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bismuthdrummer

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Not to mention we gain nothing from having the NAND be a recovery partition, as the Pandora is already designed to recover from an inserted SD card with an OS package. Going the other direction adds nothing new, aside from another option, which of course is always welcome.
 

Grench

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Ok, instead of arguing the "should we"s, I'm going to go straight to the "can we", save a lot of argument.


No, we can't.


The NAND is already formatted with a compressed file system. Everything that is stored on it effectively gets zipped up. If it is full, and you took a copy of it, zipped it up, and made that zip the only thing on it, the NAND would still be full. Almost, anyway, there's a little play for overhead and slightly inefficient compression to allow faster random access, but not as much as you're hoping for. If we have space constraints now, creating a compressed recovery partition is not going to give us a lot more space for additional features to be uncompressed to an SD card.

Thank you - a definitive answer from someone who knows helps a lot.


So, scrap the idea. Back to your regularly scheduled stuff.
 

CAZMIESTER

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Strictly booting off an SD card is disadvantageous to the average user. Once that SD card is mounted you can't unmount it. You can't remove it, can't put it into mass storage mode, there is no way to quickly and easily copy things onto it. Furthermore, it'll need to be formatted EXT which is not automatically compatible with Windows. The desire is to make the Pandora MORE friendly to Average Joe User; doing as you describe is a step away from that goal.
How come when i put an sd card like this into the caanoo it can pick it up but sd card readers cant is this a linux issue ?
 

Grench

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Strictly booting off an SD card is disadvantageous to the average user. Once that SD card is mounted you can't unmount it. You can't remove it, can't put it into mass storage mode, there is no way to quickly and easily copy things onto it. Furthermore, it'll need to be formatted EXT which is not automatically compatible with Windows. The desire is to make the Pandora MORE friendly to Average Joe User; doing as you describe is a step away from that goal.
How come when i put an sd card like this into the caanoo it can pick it up but sd card readers cant is this a linux issue ?

It isn't a Linux issue. It's a Windows issue. You most likely need to install an EXT2 driver on your Windows machine.
 
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