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Swap on flash considered harmful?
Swap on flash considered harmful?
Posted Dec 14, 2006 3:58 UTC (Thu) by xoddam (subscriber, #2322)Parent article: Playing with the OLPC
> with the wrong software, the system will just sit there and thrash.
Bash those bits and thrash to Flash!
Is it still true that Flash memory deteriorates if you write too often to
the same location? Or do storage devices these days do some kind of
block remapping to alleviate the problem (I can imagine all those FAT
filesystem superblock rewrites would push the limit otherwise...)
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Thrash to flash
Posted Dec 14, 2006 4:21 UTC (Thu) by bronson (subscriber, #4806) [Link]
That could be an awesome Jono Bacon song. :)
Swap on flash considered harmful?
Posted Dec 14, 2006 4:59 UTC (Thu) by khim (subscriber, #9252) [Link]
OLPC does not use FAT. It uses JFFS2...
Swap on flash considered harmful?
Posted Dec 14, 2006 6:16 UTC (Thu) by dberkholz (subscriber, #23346) [Link]
Newer Flash takes care of that, and JFFS2 also handles it in software.
Wear leveling
Posted Dec 14, 2006 9:31 UTC (Thu) by man_ls (subscriber, #15091) [Link]
It's called Wear leveling; read Sandisk's paper. Writing 4k every 5 seconds to flash would yield a lifetime of at least 73 years, probably 3 times as much.But anyway I agree with you: I would disable swapping. Either it fits in memory or it doesn't -- no sense in wasting the limited disk space.