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Re: CVS commit: src/sys/kern



I'll add a <aol>me too</aol> here.

On Wed, 24 Sep 2008, Thor Lancelot Simon wrote:
On Wed, Sep 24, 2008 at 01:19:43PM -0500, David Young wrote:
On Wed, Sep 24, 2008 at 01:46:34PM -0400, Thor Lancelot Simon wrote:

This also breaks products which run from flash with their filesystems mounted
read-only most of the time, but remount them read-write in order to write
back configuration data when it changes.  That is not an uncommon model
AFAIK and it poses a fairly major problem for me.

Your application sounds similar to mine.  I gave up remounting a
read-write filesystem read-only long, long ago, because if I created or
deleted and re-created as few as one or two files, remounted read-only,
and rebooted shortly thereafter, the filesystem had lost the most
recently created files.  I have probably annotated the problem report
with that information.

When is "long, long ago"?  We have not updated our sources from the NetBSD trunk
in about three months, but I haven't seen any sign of this problem.  One 
difference
may be that our configuration information is stored in a "repository" file and 
then
extracted back into a mounted-on-top memory filesystem early in boot; when we 
remount
read-write, typically the only file we update is the repository, after which we 
fsync
it and sync the filesystem before remounting r/o.

We write or alter a couple of configuration files, sync and then remount r/o. I've not seen any problems with netbsd-3 or netbsd-4. Is it believed
that this problem is a regression in -current?

--
Stephen


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