Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
On Thu, Jul 30, 2009 at 22:15, Caroline Meekscarol...@solutiongrove.com wrote: But anyway, we don't _need_ an expert. Rather an advanced linux user that can ask the right questions, read shell scripts, inspect a running system, etc. Already asked in the local linux user groups? Hi Tomeu, I'm trying to put together a wiki page taht explains where we are where we need to go coherently then I will reach out to LUGS etc. Can you help me feel confident that I have created such a page? Oops, almost miss this hidden message ;) Where is that page? Regards, Tomeu ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
On Fri, Jul 31, 2009 at 4:30 AM, Tomeu Vizoso to...@sugarlabs.org wrote: On Thu, Jul 30, 2009 at 22:15, Caroline Meekscarol...@solutiongrove.com wrote: But anyway, we don't _need_ an expert. Rather an advanced linux user that can ask the right questions, read shell scripts, inspect a running system, etc. Already asked in the local linux user groups? Hi Tomeu, I'm trying to put together a wiki page taht explains where we are where we need to go coherently then I will reach out to LUGS etc. Can you help me feel confident that I have created such a page? Oops, almost miss this hidden message ;) Where is that page? The Sugar TODO Page is where I am assembling info. Right now, I think we have 2 potential solutions within our internal capabilities. 1. Full Install 2. Open Suse solution My next step is to see if either of these are workable. I do think its technically feasible to create a stick that will withstand quite a bit of abuse if we had the experts in the field helping us. But I'm just working towards good enough for the fall at this point. The TODO page will give you a hint as to where I'm heading next. If Dave Farning thinks he can do the Clone Activity then I'll probably focus on trying to get a few more collaboration use cases working. Collaboration is so effective, cool and engaging when it works. Regards, Tomeu -- Caroline Meeks Solution Grove carol...@solutiongrove.com 617-500-3488 - Office 505-213-3268 - Fax ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
On Fri, Jul 31, 2009 at 13:50, Caroline Meekscarol...@solutiongrove.com wrote: On Fri, Jul 31, 2009 at 4:30 AM, Tomeu Vizoso to...@sugarlabs.org wrote: On Thu, Jul 30, 2009 at 22:15, Caroline Meekscarol...@solutiongrove.com wrote: But anyway, we don't _need_ an expert. Rather an advanced linux user that can ask the right questions, read shell scripts, inspect a running system, etc. Already asked in the local linux user groups? Hi Tomeu, I'm trying to put together a wiki page taht explains where we are where we need to go coherently then I will reach out to LUGS etc. Can you help me feel confident that I have created such a page? Oops, almost miss this hidden message ;) Where is that page? The Sugar TODO Page is where I am assembling info. Right now, I think we have 2 potential solutions within our internal capabilities. 1. Full Install 2. Open Suse solution My next step is to see if either of these are workable. I do think its technically feasible to create a stick that will withstand quite a bit of abuse if we had the experts in the field helping us. But I'm just working towards good enough for the fall at this point. I guess is this one: http://wiki.sugarlabs.org/go/Sugar_on_a_Stick/TODO Looks like a good start, but could you expand on your plans to recruit people to work on the file system issues? Thanks, Tomeu The TODO page will give you a hint as to where I'm heading next. If Dave Farning thinks he can do the Clone Activity then I'll probably focus on trying to get a few more collaboration use cases working. Collaboration is so effective, cool and engaging when it works. Regards, Tomeu -- Caroline Meeks Solution Grove carol...@solutiongrove.com 617-500-3488 - Office 505-213-3268 - Fax ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
I've arrived late. I've been listening to this discussion for a week. A general comment ... if any state is preserved by the children on the USB sticks, and there is no copy of the state kept elsewhere, and there is a possibility of power failure, premature removal, or other interruptions, then every software component that uses the saved state must be either capable of detecting corruption of the saved state, or graceful recovery from apparently invalid state. It seems that there are a large number of software components involved. Each one would have to be considered. Sounds like an interesting challenge. The way I would approach it is to evaluate the saved state between a working and non-working USB stick. Are these images available for analysis? Would you like technical instructions for capturing images next time the problem happens? My understanding of the Linux based Sugar software stack is that there are many components which could enter a state where they would not start. Back tomorrow. -- James Cameron http://quozl.linux.org.au/ ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
On Fri, Jul 31, 2009 at 8:34 AM, James Cameron qu...@laptop.org wrote: I've arrived late. I've been listening to this discussion for a week. A general comment ... if any state is preserved by the children on the USB sticks, and there is no copy of the state kept elsewhere, and there is a possibility of power failure, premature removal, or other interruptions, then every software component that uses the saved state must be either capable of detecting corruption of the saved state, or graceful recovery from apparently invalid state. Nod. Note further down on this page backup and file recovery is listed. That is in progress. Interestingly enough I have seen kids pull the stick out at the wrong time and that does not see to correlate with the stick failures based on observation not strong data collection. I would like to someday have a really robust solution that could recover from that sort of catastrophic failure and even go through the washing machine. I think such is possible. Right now I'd be happy if sticks rarely failed during normal usage. It seems that there are a large number of software components involved. Each one would have to be considered. Sounds like an interesting challenge. The way I would approach it is to evaluate the saved state between a working and non-working USB stick. Are these images available for analysis? Would you like technical instructions for capturing images next time the problem happens? I have both working and nonworking sticks. I could post images of them. Can you send me instructions on how to create images from MacOSX? Thanks! My understanding of the Linux based Sugar software stack is that there are many components which could enter a state where they would not start. Back tomorrow. -- James Cameron http://quozl.linux.org.au/ -- Caroline Meeks Solution Grove carol...@solutiongrove.com 617-500-3488 - Office 505-213-3268 - Fax ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
On Fri, Jul 31, 2009 at 08:41:29AM -0400, Caroline Meeks wrote: On Fri, Jul 31, 2009 at 8:34 AM, James Cameron qu...@laptop.org wrote: I've arrived late. I've been listening to this discussion for a week. A general comment ... if any state is preserved by the children on the USB sticks, and there is no copy of the state kept elsewhere, and there is a possibility of power failure, premature removal, or other interruptions, then every software component that uses the saved state must be either capable of detecting corruption of the saved state, or graceful recovery from apparently invalid state. Nod. Note further down on this page backup and file recovery is listed. That is in progress. There's also a risk that a corrupted saved state could be backed up, in such a way that a restore would return the system to a non-working state. Interestingly enough I have seen kids pull the stick out at the wrong time and that does not see to correlate with the stick failures based on observation not strong data collection. Yes, I'm worried that the cause may be more complex, and without analysis we might all be relying on hope. I have both working and nonworking sticks. I could post images of them. Can you send me instructions on how to create images from MacOSX? Sadly, no. While I have a Mac OS X system here, I don't yet know how to access a USB device at a raw block level. However, it is easy for me to explain on Linux: 1. while the device is not plugged in, identify the last block device listed in /proc/partitions, 2. plug the device in, allow five to ten seconds for settling delay, and identify the new block device listed in /proc/partitions, for instance it may appear as /dev/sda and /dev/sda1, the former is the whole device, the latter is the first partition, 3. copy the data from the whole device, using a compression program, for instance: # gzip /dev/sda usb-stick.img.gz ... where you should replace /dev/sda with whatever the result was from step 2 above. This creates an image of the whole device, which is compressed, and can be used for analysis. The ideal data set would be a working and non-working image from exactly the same version ... and as small a stick as possible ;-). -- James Cameron http://quozl.linux.org.au/ ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
Re: [Sugar-devel] Reducing Stick Failures - Was Re: [Marketing] press release opportunity...
On Fri, Jul 31, 2009 at 6:34 AM, James Cameronqu...@laptop.org wrote: A general comment ... if any state is preserved by the children on the USB sticks, and there is no copy of the state kept elsewhere, and there is a possibility of power failure, premature removal, or other interruptions, then every software component that uses the saved state must be either capable of detecting corruption of the saved state, or graceful recovery from apparently invalid state. This is a lot more basic. The current SoaS uses - FAT16 - An overlay FS in a file on FAT16 The most trivial non-100% kosher shutdown completely cooks the overlay. One serious oddity is that the overlay is mounted by something that depends on X or the gnome / sugar session, so an X crash unmounts the overlay, somtimes corrupting it. And more serious hangs or oops, did I just pull the USB stick moments have a very high chance of cooking the FAT partition itself. We have 2 brittle filesystems, one on top of eachother. The proposals if using a fully installed USB, probably using a journalled FS are definitely a step in the good direction. Once that is fixed, then it makes sense to look at the app layer that you mention. But that's the same app layer we have on the XO, and it's been handling unclean shutdowns pretty well for a while (on 0.82 at least). cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel
