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Date: Mon, 29 Oct 2007 20:51:25 +0000
From: Jamie Lokier <jamie@shareable.org>
To: =?iso-8859-1?Q?J=F6rn?= Engel <joern@logfs.org>
Subject: Re: jffs2: too few erase blocks
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Jörn Engel wrote:
> On Sun, 28 October 2007 22:59:07 -0400, David Woodhouse wrote:
> > 
> > Yes, it does. In fact, on NOR flash you get entirely synchronous
> > behaviour even _without_ explicit syncs -- effectively the same as
> > MS_SYNC.
> 
> On older ones.  There appears to be a tendency for newer flashes to
> require wbuf and hence sync.

When you say "sync", do fdatasync() / fsync() on open files and
directories flush the necessary blocks from wbuf for those
files/directories data and their inode metadata, for JFFS2?

I have been calling sync(), but I wonder if fdatasync/fsync do as they
are supposed to?

(If you know about other fses like LogFS/Yaffs/UBIFS that would be
handy, too).

Probably all are unnecessary in my specific application, as I use a
JFFS2 with cfi_cmdset_0002, which I get the impression doesn't buffer
any writes anyway.  But I like to get the application code right, in
case I change to another device.

-- Jamie