JFFS2 determine writing state

[Jörn Engel]

On Tue, 15 January 2008 17:35:10 +0000, Jamie Lokier wrote:
> 
> Oh, ok, I thought it at least merged things in the page cache like
> most other filesystems.  It seems it's more like O_DSYNC - or more
> like O_SYNC (commits metadata changed for every write too)?

I don't think there is a really good equivalent.  Writes happen
immediatly, but the changes may not become effective immediatly.  In a
way, the worst of both worlds. :)

> Is there a particular advantage, in terms of flash overhead,
> compression, or mount/gc times, to writing blocks with a particular
> size and alignment, such as 4k size and 4k offset-alignment-in-file?

4k size and 4k alignment is best for all the reasons you cited above.

> Also, does LogFS (which I want to try later) have similar
> characteristics?

At the moment, yes.  Most likely I won't get the caching part done
before LCA.

Jörn

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Victory in war is not repetitious.
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