[maemo-developers] [maemo-developers] RE: defective memory?

[From: Olivier ROLAND]

Siarhei Siamashka a écrit :
> On 9/19/06, Kimmo Hämäläinen <kimmo.hamalainen at nokia.com> wrote:
>
>> Yes, it would need to be reproducible in several different devices. The
>> guy here that tried to reproduce it currently thinks that Siarhei's unit
>> is broken.
>
> Yes, I also think that the probability of my device being broken is
> quite high. A certain (small) fraction of other Nokia 770 owners are
> probably having the same problem. Does it make the device completely
> useless? Of course no, my device works almost fine, it only crashes
> and reboots sometimes, I also has filesystem corruption several times
> (now even switched mmc filesystem to ext3, don't know if it would help
> much though). So the device can be surely used as a book reader,
> internet browser and serve other tasks. Other (small) fraction of
> users who got 'white screen of death' were surely less lucky.
>
> What can be done about this if the defective memory problem gets
> confirmed. I see three possible ways:
> 1. 'Ignorance is a bliss' - just do nothing, those who don't know
> about the problem will not worry about it :) The device will just
> crash or reboot occasionally, some more unlucky users having more
> annoying crashes will complain in the forums providing some bad PR.
> 2. Distribute some diagnostics software that will help to identify
> memory problems and repair/replace defective units, that will have
> some expences, but will improve overall reliability and reduce the
> number of negative publicity.
> 3. Add some (un)official support for working around bad memory regions
> using technology something similar to BadRAM, in this case most of
> such units will be completely usable.
>
> In general, bad memory problem is quite common for x86 pc's, but there
> is an excellent tool for memory diagnostics - memtest86. It helped me
> quite a number of times, also I always advice everyone having
> stability issues to run it first. I don't know how the reliability of
> memory chips used in embedded devices compares to the reliability of
> memory from normal desktop computers, but bad memory seems to be one
> of the most frequently encountered hardware problems.
If your device is broken then mine is also.
I don't think at all that we speak about (small) fraction because 
majority of users won't even notice the problem.
My device seem stable until I stressed it. And stressed it is not a 
"condition suffisante" to make the problem happen.
When I have time, I will make extensive test on my device to check 
exactly when the problem occur.

My doubt about "small fraction" are probably driven by the fact that I 
was "hit" by 'white screen of death' 4 weeks after buying the device.
So I guess that during the reparation my 770 was checked (again) by the 
conventional Nokia diagnostic.
I conclude that the conventional Nokia diagnostic doesn't detect the 
problem.

To make things clear, I don't want to make negative publicity at all. I 
enjoy this device a lot and I've ported Streamtuner on it with lot of 
great feedback from users.

My 2 cents.

PS: I don't know what is "the conventional Nokia diagnostic" but as far 
as I know there is always a "conventional XXX diagnostic" in reparation 
centers.

Olivier ROLAND