Re: intermediate summary of ext3-2.4-0.9.4 thread

Jan Harkes
2001-08-03T16:20:50Z

On Fri, Aug 03, 2001 at 02:14:06AM +0200, Matthias Andree wrote:
> On Fri, 03 Aug 2001, Anton Altaparmakov wrote:
> > filedescriptor to be synced to disk, the ONLY possible way to do this it to
> > sync the parent directory in order to commit the file name to disk. On some
>
> Do I really need to sync the WHOLE parent directory? Not just the
> relevant part? My directories hardly have only 1 disk block.

Only dirty blocks are written back to disk, i.e. the parts of the
directory that were modified by adding/removing names. It should be
pretty efficient.

> > to explicitly sync the directory filedescriptor afterwards.
>
> Which is non-portable and will not be done by many application
> programmers which just use chattr +S instead (makes things S)afe and
> S)low) - and spoil performance that way since it makes not only
> directory writes synchronous, but file (data) writes as well.

"chattr +S" is about as portable as adding fsync(parent), or even worse
as it only works on an ext2 file system. So I'm assuming that this is
just a nice exercise in annoying people.

Jan