Re: FAT vs jFFS2 for NAND.

[Charles Manning <manningc2@actrix.gen.nz>]

On Sunday 28 May 2006 14:58, Han Chang wrote:
> Hi there,
>
> My first question is that if I can use FAT file system for NAND. If yes,
> what are the pros and cons for using FAT vs. JFFS2.

FAT needs to work with a block driver, so you can use FAT if you use a block 
driver on top of the NAND. 

You can use JFFS2 or YAFFS as true flash file systems (ie that work directly 
with the NAND).


Pros of FAT:
*) If you're using this on a device that must look like a USB mass storage 
device, or similar, then FAT is easier for people to use.
*) Have a smaller RAM footprint than JFFS2 or YAFFS. JFFS2 and YAFFS both use 
ram to build runtime look-up trees. 
*) FAT file systems will typically mount faster than JFFS2 and YAFFS, though 
both YAFFS and JFFS2 mount times have reduced significantly in recent weeks.

Pros of YAFFS or JFFS2:
*) Faster.  YAFFS is faster than JFFS2 which should be faster than FAT.
*) YAFFS and JFFS2 are both log structured fs which make them far more robust 
against corruption than FAT.
*) YAFFS abd JFFS2 support features like links which are missing from FAT.

-- Charles