Jan Koester posted on Fri, 30 Dec 2016 13:17:37 +0100 as excerpted: > sudo btrfs filesystem df /mnt > Data, RAID6: total=1.22TiB, used=0.00B > System, RAID6: total=96.00MiB, used=0.00B > Metadata, RAID6: total=8.25GiB, used=80.00KiB > GlobalReserve, single: total=512.00MiB, used=8.00KiB Expanding on what I already mentioned in passing (hoping it wasn't the case), raid56 mode (so including your raid6) remains quite unstable, with known problems that make it unsuitable for the sort of purposes people normally run parity-raid for. So it's actively negatively recommended unless you're running it for the specific purpose of trying to help the devs work out the problems with it, using only throw-away-value test data in case those problems eat it, which unfortunately they have a significantly real chance of doing, with raid56 at this point. So you need to get off of it ASAP, and hope any data that wasn't already throw-away-value, doesn't end up being thrown away anyway, in the process. Unfortunately, as I said in the earlier post, I'm just a user, tho a list regular, myself, not a dev. And I've been staying well away from raid56 /because/ of these problems (as well as because it didn't fit my use-case in the first place), so other than noting the severity of the issues, I've not really been paying attention to the various threads with people trying to fix the problems and save at least some of their raid56 stored data. So if you want to try to save the data, you'll need help from a dev or higher level expert, or failing that, at least to examine the last couple 2-3 months worth of list threads and find the raid56 ones with methods to try to save what can be saved, and possibly to patch at least some of the problems in ordered to not make the problem worse while you're doing so. But it's going to require some reasonable technical know-how to try to do that, as well as the time and hassle, so honestly, unless that data's /really/ worth it, it may be better to simply cut and run, doing a fresh mkfs and being done with btrfs raid56 for now, without spending more time on it, only to find you can't save much anyway. Tho if it's worth it to you, you may be able to save much of it, but you could spend a month's man-hours doing it too and possibly still come up empty. Plus be careful, because stuff like scrub that would normally help, can make the problem much much worse in the case of raid56 ATM. Yes, the problems with it ATM *are* that bad. Unfortunately. There's actually talk of scrapping the code (almost?) entirely and starting over again, as there's a real question as to whether it can even be properly fixed, tho I'm not sure it will come to that. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
