On Mon, Aug 24, 2009 at 11:19:01AM +0000, Florian Weimer wrote: > > +* don't damage the old data on a failed write (ATOMIC-WRITES) > > + > > + (Thrash may get written into sectors during powerfail. And > > + ext3 handles this surprisingly well at least in the > > + catastrophic case of garbage getting written into the inode > > + table, since the journal replay often will "repair" the > > + garbage that was written into the filesystem metadata blocks. > > Isn't this by design? In other words, if the metadata doesn't survive > non-atomic writes, wouldn't it be an ext3 bug? So I got confused when I quoted your note, which I had assumed was exactly what Pavel had written in his documentation. In fact, what he had written was this: +Don't damage the old data on a failed write (ATOMIC-WRITES) +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Either whole sector is correctly written or nothing is written during +powerfail. + +.... So he had explicitly stated that he only cared about the whole sector being written (or not written) in the power fail case, and not any other. I'd suggest changing ATOMIC-WRITES to ATOMIC-WRITE-ON-POWERFAIL, since the one-line summary, "Don't damage the old data on a failed write", is also singularly misleading. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html