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Re: run debian off usb flash drive

On Sun, 7 Mar 2004 13:30, Marc Singer <elf@buici.com> wrote:
> Most of the flash parts are rated for 100K erase cycles per 128KiB
> block (StrataFlash).  Cheap hard drives are usualy waranteed for only
> one year.  Assuming the best case for flash, and worst case for a hard
> drive, the flash device can take about 250 block erase cycles/day in a
> year of continuous use.  The wear-leveling flash filesystems will

250 erases per day on a single is not a likely amount of load for a laptop 
provided that there is plenty of spare space.

Also running a utility every few months to move everything around might be 
helpful.  Otherwise the part of the storage containing /bin/bash might be 
almost unused while ~/Mail starts dieing.

Last time I checked it seemed that JFFS2 (the wear-levelling file system) only 
worked on flash memory not on flash devices with ATA or USB interfaces.  The 
flash devices with ATA or USB interfaces are SUPPOSED to do wear levelling 
internally, but rumor has it that they often don't.

If you can't get JFFS2 then you have a choice of ReiserFS, Ext2/3, etc.  The 
problems with these file systems is that they have Inode tables, journals, 
and other data structures that are accessed a lot in fixed locations.  This 
should be OK if the hardware does wear levelling, but will be a killer if 

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