On 2011-02-07, at 06:15, Lukas Czerner wrote: > On Thu, 3 Feb 2011, Andreas Dilger wrote: >> This patch adds the ability to skip zeroing the journal on disk. This can >> significantly speed up mke2fs with large journals. At worst the uninitialized >> journal is only a very short-term risk (if at all), because the journal will >> be overwritten on any new filesystem as soon as any significant amount of data >> is written to disk, unlike lazy_itable_init which can leave uninitialized >> itable blocks indefinitely (in the absence of the kernel init thread). > > I think that we can skip the journal zeroing if the underlying device, > or the journal device supports discard, and advertise that discard > zeroes data. It is the same behavior as in the case of inode tables and > it would be nice to have the same thing for journal. Are you planning to > implement this as well ? That detection didn't exist when I originally wrote that patch. It definitely makes sense to default to not zeroing the journal if discard has been done. Cheers, Andreas -- 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
