Re: writing file to disk: not as easy as it looks

[Pavel Machek <pavel@suse.cz>]

On Wed 2008-12-03 18:43:18, Mikulas Patocka wrote:
> > On Wed, Dec 03, 2008 at 09:46:40AM +0100, Pavel Machek wrote:
> > > Yes. fsync() seeems surprisingly high on Rusty's list of broken
> > > interfaces classification ('impossible to use correctly').
> 
> BTW where is that list.

http://ozlabs.org/~rusty/index.cgi/tech/2008-04-01.html

> > To be fair, fsync() was primarily intended for making sure that the
> > data had been written to disk, and not necessarily as a way of making
> > sure that write errors would be properly reflected back to the
> > application.  As you've pointed out, it's not really adequate for that
> > purpose.
> 
> Well, what else do you want to use for databases? (where crashing the 
> whole computer makes less damage than pretending that transaction was 
> committed while it wasn't).

I guess we could modify fsync() to fail if there was _ever_ write
problem on same filesystem. That would make it "safe". And as
ext2/ext3 can't handle metadata write errors anyway... maybe that
should be done?
									Pavel
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