CommentStreams:76e5030c0894d218f9cfbdc96d18c215

Hi, Maffblaster, I saw your edit and some things didn't feel right, so I would like to discuss them with you: Let me know your thoughts - I'm happy to merge this info, but didn't want to do it without consulting first. Cheers!
 * Are you certain that advising a risky but "safe" device removal by shutting down the system is wise? We are not saying that you have to have a redundant profile - basically if you do this on anything that isn't at least RAID1, you will lose data.
 * Are you sure that it is faster to remove a device this way? Your solution indeed mentions that you have to mount the fs in degraded mode, and indeed then you have to fix the fact that you removed a device by scrubbing the fs - isn't this what "btrfs de remove" will do gracefully anyway? In what way you save time?
 * It is worth mentioning what you do in case the device does fail and cannot be recovered - degraded mode (and a few other tricks) will certainly be needed to gain access to the fs again.
 * Since you also mentioned that the device could be replaced, it's probably high time that we introduce "btrfs de replace", which is definitely the fastest way to replace a device, with the "small" caveat of having to add the additional device to the fs in advance.