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padishah_emperor
With the release of the C1000 which like other C series machines, uses internal flash memory, I was thinking what a naff idea it is. After all, flash wears down and eventually dies so the only logical reason for it in my mind is that people will have to keep buying new hardware. Using an internal microdrive doesn't solve the idea as that can develop bad sectors and unless it's replaceable in the 3000, it leaves the machine a brick. I know the arguements about levelling etc. but even on my old C860, it started to deteriorate since I was coding and compiling and using swap maybe, the 512MB lexar card I had died a little while after my C860 went. That card wasn't even 18 months old.

So, I was wondering (and this is semi-directed at Anton wink.gif ), can't a ROM be built to move all read/write operations to a CF card/Microdrive or SD card? Selectable by the user during the flash operation? Mounting the internal flash as read only? I'm not too knowledgeable about building ROMs etc on the Z so maybe someone out there knows or would like to share their opinions on the wisdom/merits of slowly rotting flash.

I'm quite attracted to the C1000, even with a VGA screen tongue.gif but the flash thing is a major issue for me, I'd really like the option to wear out a replaceable item rather than a non-replaceable one.

-Francis
JohnKiniston
I would think that if one is willing to sacrafice space on their external storage cards that they could just make a couple filesystems and mount them ontop of the internal flash, That would redirect any writes to what would be the internal flash to the external filesytem.

Doing so would not cause any writes to the internal flash either as it should be a kernel function to keep track of mount points.

If your external storage had a fault your devcie would still work using the internal storage.
maslovsky
My personal opinion - I don't really care about internal flash life time (I think it will be long enough for my needs) and my next Zaurus will mostly likely be C1000 smile.gif
adf
I tend to agree.. .. how long do we keep these things before we upgrade, as a rule? How does that compare to flash life?

And, If one can build the fs on an external device before the flash fails, could it not be done after, and if not, wouldn't that imply that the thing wouldn't boot no matter where most of the executables lived?

If the life of memory were the issue, shouldn't the built-in microdrive be even scarier?

though I think my next zaurus hasn't been built yet. cool.gif
iamasmith
I have to agree with Maslovsky on this, unless you are putting a page file on the flash then I doubt that you are going to generate enough writes over a period of ownership for it to be an issue.

I think you are more likely to experience battery problems well before you start to see flash problem.

Note that some of the early 5500 ROMs offered an SD based home structure, not sure if they mounted everything RO but that would simply be a waste of resources in something like the SL-C860 with 128Mb flash,

Personally I think it's still much better than the Palm/PocketPC position of running everythig from RAM - especially if you are going to 'push the envelope' from time to time.

My wife has given up on PDAs and returned to Filofax because she originally had a Handspring which you only needed to charge every few months - when that packed in I gave her a Sony Clie that I had knocking around and she couldn't get to grips with the fact that she needed to charge it at least every couple of weeks and consequently lost her data a couple of times - NAND flash therefore has some distinct benefits but she just can't be bothered with PDAs any more and wouldn't carry anything as big as a Z anyway.

- Andy
padishah_emperor
QUOTE(maslovsky @ Mar 12 2005, 08:51 AM)
My personal opinion - I don't really care about internal flash life time (I think it will be long enough for my needs) and my next Zaurus will mostly likely be C1000 smile.gif
*

Well Anton I guess that is the answer that counts biggrin.gif tongue.gif


QUOTE(adf @ Mar 12 2005, 09:27 AM)
If the life of memory were the issue, shouldn't the built-in microdrive be even scarier?
*

Indeed, I think I mentioned it. I've had plenty of flash devices fail - and even more hard drives fail! That's why these things should be replacable by anyone who is brave enough to use a screwdriver. I know my microdrive will die probably within a year but I can budget for a replacement and the critical thing is it takes a second to swap it out of the CF port.


QUOTE(iamasmith @ Mar 12 2005, 10:10 AM)
I have to agree with Maslovsky on this, unless you are putting a page file on the flash

Which I do as needed
QUOTE(iamasmith @ Mar 12 2005, 10:10 AM)
then I doubt that you are going to generate enough writes over a period of ownership for it to be an issue.

I think you are more likely to experience battery problems well before you start to see flash problem.

But that is usually replaceable, even on my machine where it's sealed in, it's a simple screwdriver job
QUOTE(iamasmith @ Mar 12 2005, 10:10 AM)
Note that some of the early 5500 ROMs offered an SD based home structure, not sure if they mounted everything RO but that would simply be a waste of resources in something like the SL-C860 with 128Mb flash,

But would extend the life
QUOTE(iamasmith @ Mar 12 2005, 10:10 AM)
Personally I think it's still much better than the Palm/PocketPC position of running everythig from RAM - especially if you are going to 'push the envelope' from time to time.

My wife has given up on PDAs and returned to Filofax because she originally had a Handspring which you only needed to charge every few months - when that packed in I gave her a Sony Clie that I had knocking around and she couldn't get to grips with the fact that she needed to charge it at least every couple of weeks and consequently lost her data a couple of times - NAND flash therefore has some distinct benefits but she just can't be bothered with PDAs any more and wouldn't carry anything as big as a Z anyway.

- Andy
*

Yes and for a normal PDA I'd agree, but how many of us what to use it for more, X for example, C compiling - I used to do that on a Z, using the swapfile applet which Cacko used to have. I hammer flash as I want to use the device for more than PIM stuff. Sadly, I fear my current device which uses RAM over flash is still the only device which is can meet my demands, real shame - I was soooo close to ordering a C1000. I just don't rate flash, despite the arguements, I've killed too many flash devices - they cannot take the punishment blink.gif

If I may digress for a moment, with my YP3700, it uses SDRAM for r/w operations everything else is r/o from a cramfs. There IS a flash memory but it can't get hammered as it's used to backup PIMs (which is more useful to me than backing it up to a PC) and putting apps to be pre-installed in the event of a full reset. I think that is a much better design and yes, the battery will be the first element to wear out. But with care, I know I could still be using this in 10 years from now. End digression. wink.gif

I think the Z can last much longer by mounting it's internal flash r/o - it does not need to be wasteful, fill it up with apps! -a simple control panel applet could lock/unlock it!- and move the r/w ops to a user replaceable element like SD which is formatted with a wee GUI utility as jffs2 and/or a ramdisk. I believe it will extend the device's life and allow much heavier usage. IMHO.

Sincere thanks to everyone who answered smile.gif I'm going to stick with what I have until I find another device which will do what I want, after spending over £750 on a device I was too scared of breaking, I'm severely stung. The ~£300 C1000 is attractive, I could even keep my glasses on and put up with VGA, but I plan on buying with a long view - I still have my HP200LX, if it were flash based it would be dead by now for sure.

I'd not realised PPCs were non-flash based, can you elaborate? Or point me to info about this? If I can compile on it, then sadly that would be up for consideration as I understand they can work with Macs nowadays.

Sincere thanks all.
iamasmith
QUOTE(padishah_emperor @ Mar 12 2005, 01:10 PM)
...
I'd not realised PPCs were non-flash based, can you elaborate? Or point me to info about this?....
*


The flash on a PocketPC is a read only image whilst running the PocketPC OS, however, some with excess amounts of Flash offer a partition as use for user storage (iPAQ 3970 etc..)

This is how I understand the PocketPC...

The OS storage and Execution is made up of XIP regions (execute in place) so the programs aren't copied to RAM when they are executed. Obviously user apps installed in RAM will execute in RAM... typically all the ROM based stuff runs from ROM and creates state data in RAM.

Typically you don't install anything to flash except for ROM based hotfixes which program individual XIP regions independently so you can produce reasonably generic updates that target a fix for a ROM based app (Pocket Word etc.) without targetting the OEM specific stuff.

User applications are installed into RAM and the installation image is kept seperate from state data. Reset the PocketPC and the state data is discarded whilst the apps that are installed in RAM are retained... this helps as long as you don't lose battery power.

However, put Familiar Linux on an iPAQ PocketPC and you use the flash as storage just as you do for a Z.

I think if you are going to hack around with the kernel and as I say 'push the envelope' on these devices then you can't view it as a 'consumer device' like the PocketPC is you want more certainty that you aren't going to lose your apps and data if RAM gets zero'd for some reason...

- Andy
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