Re: Implementing writepage

David Woodhouse
2003-10-26T10:25:57Z

On Sun, 2003-10-26 at 11:40 +1300, Charles Manning wrote:
> It's a matter of what software they're using. Debian apt-get is the current
> woesome application. Some people have vast YAFFS fs (512Mbytes or more) and
> are starting to think of it as a real disk equivalent rather than just a
> little pokey place to store a few configs. This means they want to run
> regular software.

While obviously YAFFS exists because you don't always make the same
choices as me, I'd encourage you to resist calls to implement shared
writable mmap on flash, or at least to make it an optional feature which
is omitted by default. Otherwise, people might actually use it :)

The life time of flash is limited, and users should endeavour to reduce
the number of writes even if the media become big enough that the rest
of the pain of using flash is alleviated.

Shared writable mmap can cause a rewrite of a whole page every time a
single byte is changed; explicit writes are almost always going to be a
more efficient use of the flash.

Your file system is not broken; your application author is. Mend that
instead. :)

--
dwmw2