Re: Writing large files onto sync mounted MMC corrupts the FS

[Jarkko Lavinen]

On Thu, Jun 02, 2005 at 10:52:57AM +0400, ext Artem B. Bityuckiy wrote:
> So, we should first ask whether this happens with *new* MMC cards or
not.

Flash manufactorers typically claim 100k erase cycles -- some even 1M.
If FAT is updated after each written 512 byte block, filling 64MiB
card in synchronous mode would cause over 100k FAT updates.  One
couldn't even fill a new 64MiB card without already breaking it.

With asynchronous mount, one could limit the dirty_ratio from proc to
reduce the sync time against sudden power loss. But wouldn't this have
the same adverse wearing effect as with synchronous mode once the
dirty_ratio is hit and writing still proceeds?

Jarkko Lavinen
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