[Lazarus] Using Lazarus on Embedded Linux?

[Henry Vermaak]

On 28/09/10 10:18, Michael Schnell wrote:
> Independent from the kind of the hardware interface to the card, the
> problem is that
> - in Linux you think you are safe if you unmount the file system before
> powering off
> - when using a journaling file system you are sure that you always can
> power off the system and when restarting the file system will restart
> after the latest completed written transaction, with all previous data
> being safe and a clean file system structure.

No.  If you have a disk that does out of order write caching, you will 
have to enable barriers (which are not enabled on ext3 by default, for 
example).  Then you may still have the problem of some disks not 
implementing the flushing correctly, at which point you will have to 
disable the write caching, which will have a big performance impact.

My point is that you are always at the mercy of your device (not just 
with sd/mmc).  A good sd/mmc will implement a log structured file system 
in the translation layer that won't be prone to data loss.

These are corner cases, though, and I fear that we're very far off topic 
again.

Henry