[Sugar-devel] [Marketing] press release opportunity...

[Walter Bender]

Begin handwaving.

LiveUSB came from the world of LiveCD and with it came an "overlay"
concept to enable writing in what had been a read-only world. It is
not clear that the approach was intended for more than demonstration
purposes, in order to show off the power of Fedora Linux. That would
suggest that in the long run, we may need to revisit the way in which
we manage user data on our images.

End handwaving.

-walter

On Wed, Jul 29, 2009 at 7:46 PM, Caroline
Meeks<caroline at solutiongrove.com> wrote:
>
>
> On Wed, Jul 29, 2009 at 3:18 PM, Gary C Martin <gary at garycmartin.com> wrote:
>>
>> On 29 Jul 2009, at 04:10, Caroline Meeks wrote:
>>
>>> This is a good idea!
>>>
>>> Can I also ask you and Tomeu to help me with another, complimentary
>>> approach?
>>>
>>> As I hiked up the mountain on the weekend I got a lecture from one of my
>>> friends on different file system options and journaling.  He has some time
>>> to help us.  Today at the Expo I went to I met someone who had one of the
>>> patents on USB sticks.  She is also willing to help us.
>>>
>>> I'd like to get our problems defined, resources and documentation linked
>>> up and then put together some specific requests for help that I can put out
>>> to my linkedin, facebook, and APO networks.
>>>
>>> Can you guys help me create the wiki pages that would let people
>>> understand our problems and find what they need to learn easily for some of
>>> the specific problems we don't know how to solve.
>>
>> The most authoritative and frightening item I've read on this is from
>> Mitch:
>>
>>        http://wiki.laptop.org/go/How_to_Damage_a_FLASH_Storage_Device
>>
>> There was a detailed discussion thread back in February at:
>>
>>        http://lists.laptop.org/pipermail/devel/2009-February/022987.html
>>
>> I'm sure this is not the only culprit, but it's likely an important one.
>>
>> I'm no expert in the live image process but here's my current random
>> theory for the login screen case anyway (to be proven wrong so we can move
>> on please :-) A live image has a kind of overlay file where the actual users
>> changes are being written, if a kid unplugs too early, or hits some other
>> media write issue, that overlay could be corrupted. Likely loosing all user
>> changes to the original base image (and some), the stick would still boot,
>> but bail out when it hits the corrupt overlay. Dropping the user at a login
>> prompt (but with nothing to login to as that part is corrupt). End of random
>> theory.
>
> This makes sense to me and I added it to the wiki.
> http://wiki.sugarlabs.org/go/Sugar_on_a_Stick/TODO#Sticks_are_dieing_a_lot_-_Make_sticks_more_robust
>>
>>
>> You'd need to carefully analyse the broken stick images to resolve this
>> one. Not sure of the tools you'd need.
>
> Maybe.  I am currently very suspicious of our file formatting. I want to
> know how it works and why it was chosen. then I want to find out why Open
> Suse and other distributions picked their choices.
>
> I don't have any information but its feeling like we have a "fine crystal"
> file format and what we want is a file structure that wraps the files in
> hard plastic so they will be ok even if a few bytes are disturbed.
>
> Hopefully we'll get more info. Right now I feel like all I know is how
> little we know. :)  Which is actually a useful piece of information.
>>
>>
>> Regards,
>> --Gary
>>
>
>
>
> --
> Caroline Meeks
> Solution Grove
> Caroline at SolutionGrove.com
>
> 617-500-3488 - Office
> 505-213-3268 - Fax
>



-- 
Walter Bender
Sugar Labs
http://www.sugarlabs.org