On Thu, 2012-08-16 at 03:09 -0600, Andreas Dilger wrote: > On 2012-08-16, at 1:54 AM, Javier Marcet wrote: > > I'm in the process of setting up a new software raid with four 3TB disks. > > So far I'm doing the tests using also bcache on a 60GB partition on a 120GB > > SSD. Everything is protected by a UPS. > > > > On the software side: self compiled kernel 3.5.1 and util-linux 2.20.1 > > > > Thus far, ext4 is doing really really well but for one thing, the mount > > time. At the moment I'm testing a RAID5 which makes the partition 8.2TB. > > > > ext4 takes: > > $ time mount /mnt/raid > > 0.00s user 79.49s system 92% cpu 1:26.25 total > It is a bit strange that _mounting_ uses 92% CPU. Hmm, there was a bug > reported for 3.5.1, see "Re: Upgraded from 3.4 to 3.5.1 kernel: machine > does not boot", and reverting the patch with git commit hash > "8aeb00ff85ad25453765dd339b408c0087db1527" resolved the problem. This > slowdown was only seen with larger devices. I've been seeing this as well, the symptom being the boot time on my computer going from <5s to ~20s while my 6TB ext4 filesystem mounts. I'll try reverting this patch; hopefully that helps. Is there any fix for this issue queued up for an upcoming stable release? It still reverts cleanly on 3.5.2. -- Calvin Walton <calvin.walton@xxxxxxxxxx> -- 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
