multiple MTD partitions

[Ivan Krstić]

On Dec 16, 2007, at 11:40 PM, John Watlington wrote:
> I'm curious how you measured this, as the underlying hardware only
> supports a max. transfer rate of around 20 MiB/s...


As Artem mentioned, UBIFS employs a write-back cache, meaning writes  
aren't flushed to the underlying medium immediately; pages are instead  
marked dirty in the page cache and written back when evicted.

This makes a hell of a lot of sense. In a synchronous filesystem like  
JFFS2, constant and repeated writes to the same single page will keep  
pummeling the underlying flash needlessly. With UBIFS, such writes  
succeed instantly but only cause a write/erase cycle on the flash to  
be triggered when the page gets kicked out of the page cache either  
because the RAM is needed or because of the kernel thread performing  
dirty page writeback on a timer.

--
Ivan Krstić <krstic at solarsail.hcs.harvard.edu> | http://radian.org