Swapping to MMC (Was: To swap or not to swap)

Wojciech Puchar wojtek at wojtek.tensor.gdynia.pl
Tue Dec 2 13:14:07 PST 2008

> I put in your opinions in kinda pros or cons to swap in Asus Eee PC like following:
> Pros: 1) System requires swap. Period.

it doesn't.

> Cons: 1) Since SSD is manufactured have limited lifetime (around 100,000
10000 for MLC flash it uses. after every rewrite flash gets less reliable 
and keeps data for shorter time.
new flash chip guarrantes 10 years data persistency using standard error 
correction, after 9000 rewrites it's about 1 year etc.

and: SSD "disks" emulates disks instead of using flash-designed 
filesystem. they do LOTS of extra writes for "worn up management", mapping 
tables. you can safely assume 2 times more data written in reality than 

assuming 4GB flash, 10000*4GB/2=20TB of writes and flash is dead.

not that much with swapping IO ranged in megabytes/s

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