On Jul 30, 2008 11:14 -0400, Mike Snitzer wrote: > On Tue, Jul 29, 2008 at 10:52 PM, Hidehiro Kawai > <hidehiro.kawai.ez@xxxxxxxxxxx> wrote: > > If the journal doesn't abort when it gets an IO error in file data > > blocks, the file data corruption will spread silently. Because > > most of applications and commands do buffered writes without fsync(), > > they don't notice the IO error. It's scary for mission critical > > systems. On the other hand, if the journal aborts whenever it gets > > an IO error in file data blocks, the system will easily become > > inoperable. So this patch introduces a filesystem option to > > determine whether it aborts the journal or just call printk() when > > it gets an IO error in file data. > > > > If you mount a ext3 fs with data_err=abort option, it aborts on file > > data write error. If you mount it with data_err=ignore, it doesn't > > abort, just call printk(). data_err=abort is default, because > > people have used this error handling policy for three years. > > Thanks for making this configurable! > > But given how surprised many of us were when we found out that > jbd/ext3 has been aborting on file data blocks isn't this our chance > to correct that long-standing oversight? Shouldn't the default be > data_err=ignore? Or would changing this behavior cause more harm than > good? > > I don't feel strongly either way, having the "data_err" option makes > this issue moot for me, but I figured I'd raise the question (in the > interest of review). Yes, good point. I don't think any of the ext3 maintainers were aware that the 3-years-old patch had introduced "abort on data error" behaviour. The default for ext4 is only now going to errors=remount-ro from errors=continue (as it is on ext2/3) so I think it is inconsistent to have the journal abort on data errors when the filesystem itself does not. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
