Weekly edition	Kernel	Security	Distributions	Contact Us	Search
Archives	Calendar	Subscribe	Write for LWN	LWN.net FAQ	Sponsors

Optimizing Linux with cheap flash drives

Posted Feb 19, 2011 5:00 UTC (Sat) by eru (subscriber, #2753)
In reply to: Optimizing Linux with cheap flash drives by jengelh
Parent article: Optimizing Linux with cheap flash drives

And lose all the features of a modern POSIX filesystem?

Just resurrect the UMSDOS filesystem!

(Log in to post comments)

Posted Feb 19, 2011 8:41 UTC (Sat) by arnd (subscriber, #8866) [Link]

It seems that Samsung have done something like this with their RFS (Reliable FAT file system) that they use on a lot of phones with eMMC storage.

Unfortunately, their implementation has a lot of other performance problems and, worse, it's not even available under a GPL compatible license.

Optimizing Linux with cheap flash drives

Posted Feb 22, 2011 17:34 UTC (Tue) by ttonino (subscriber, #4073) [Link]

My Samsung Galaxy S shows:

On the NAND flash with a software translation layer:
/ rootfs ro,relatime
/mnt/.lfs j4fs rw,relatime
/system rfs ro,relatime
/dbdata rfs rw,relatime
/cache rfs rw,relatime

On the internal SD device:
/data rfs rw
/mnt/sdcard vfat rw,dirsync,noatime,nodiratime
/mnt/sdcard/external_sd vfat rw,dirsync,noatime,nodiratime

Thus, rfs and normal vfat are both used. The rfs description reminded me of the phase tree FAT implementation that was going around a long time ago.

The software translation for the NAND flash is GPL.