Adam Borowski posted on Wed, 01 Feb 2017 12:55:30 +0100 as excerpted: > On Wed, Feb 01, 2017 at 05:23:16AM +0000, Duncan wrote: >> Hans Deragon posted on Tue, 31 Jan 2017 21:51:22 -0500 as excerpted: >> > But the current scenario makes it difficult for me to put redundancy >> > back into service! How much time did I waited until I find the >> > mailing list, subscribe to it, post my email and get an answer? >> > Wouldn't it be better if the user could actually add the disk at >> > anytime, mostly ASAP? >> > >> > And to fix this, I have to learn how to patch and compile the kernel. >> > I have not done this since the beginning of the century. More >> > delays, >> > more risk added to the system (what if I compile the kernel with the >> > wrong parameters?). >> >> The patch fixing the problem and making return from degraded not the >> one- >> shot thing it tends to be now will eventually be merged > > Not anything like the one I posted to this thread -- this one merely > removes a check that can't handle this particular (common) case of an > otherwise healthy RAID that lost one device then was mounted degraded > twice. We need instead a better check, one that sees whether every > block group is present. > > This can be done quite easily, as as far as I know, the list of block > group is at that moment fully present in memory, but someone actually > has to code that, and I for one don't know btrfs internals (yet?).
I didn't mention it because you spared me the trouble with your hack- patch that did the current job, but FWIW, there's actually a patch that does per-chunk testing as you indicate, but it got merged into a longer running feature-add project (hot-spares, IIRC), and thus isn't likely to be mainline-merged until that project is merged. But who knows when that might be? Could be years before it is considered ready. Meanwhile, perhaps it's simply because I'm not a dev and am not appreciating the complexities of some detail or other, but as demonstrated by the people who have local-merged that patch to get out of just this sort of jam, as well as the continuing saga of more and more people appearing here with the same problem, it could be an arguably high priority fix on its own, and should have been reviewed and ultimately mainline-merged on its own merits, instead of being stuck in someone's feature-add project queue for potentially years, while more and more people who could have definitely used it have to either suffer without it or go and find and local-merge it themselves. Even if this feature is critical to the longer term feature, merge of this little one now would make the final patch set for the longer term feature that much smaller. But that's a btrfs-using sysadmin's viewpoint, not a developer viewpoint, and it's the developer's doing the work, so they get to define when and how it gets merged, and us non-devs must either simply live with it, or if the circumstances allow, fund some dev to have our specific interests as their priority and take care of it for us. Meanwhile, perhaps I should have bookmarked that patch at least as it appeared on-list, but I didn't, so while I know it exists, I too would have to go looking to actually find it, should I end up needing it. In my defense, I /thought/ the immediate benefit was obvious enough that it would be mainline-merged by now, not hoovered-up into some long-term project with no real hint as to /when/ it might be merged. Oh, well... -- 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
