Theodore Tso wrote: > On Aug 20, 2010, at 5:41 PM, Eric Sandeen wrote: > >> If a device supports discard -and- returns 0s for discarded blocks, >> then we can skip the inode table initialization -and- the inode table >> zeroing at mkfs time, and skip the lazy init as well since they are >> already zeroed out. >> >> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> > > This needs to be configurable in /etc/mke2fs.conf. Without naming > the manufacturer, I'm aware of at least one device which claims that > discard works, and will even return zeros --- but after a power > cycle, if the block has not been reallocated, will once again return > the old, pre-discard values that had been stored in that block. > > In other words, the discard is not power-cycle persistent... > > -- Ted > > yes, I've seen issues like that too. TBH in that case I'd rather just drop the patch than make another tunable for the user to figure out... Making tunables for every permutation of broken hardware doesn't scale IMHO. Users will get it wrong often as not, if they even know it's there (they'll find out it's there via some web forum or other, and it'll become a meme like "set this to go faster" rather than understanding all the implications.) -Eric -- 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
