This is a torture test, no data is at risk. Two devices, btrfs raid1 with some stuff on them. Copy from that array, elsewhere. During copy, yank the active device. dmesg shows many of these: [ 7179.373245] BTRFS error (device sdc1): bdev /dev/sdc1 errs: wr 652123, rd 697237, flush 0, corrupt 0, gen 0 Why are the write errors nearly as high as the read errors, when there is only a copy from this device happening? Is Btrfs trying to write the read error count (for dev stats) of sdc1 onto sdc1, and that causes a write error? Also, is there a command to make a block device go away? At least in gnome shell when I eject a USB stick, it isn't just umounted, it no longer appears with lsblk or blkid, so I'm wondering if there's a way to vanish a misbehaving device so that Btrfs isn't bogged down with a flood of retries. In case anyone is curious, the entire dmesg from device insertion, formatting, mounting, copying to then from, and device yanking is here (should be permanent): http://pastebin.com/raw/Wfe1pY4N And the copy did successfully complete anyway, and the resulting files have the same hashes as their originals. So, yay, despite the noisy messages. -- Chris Murphy -- 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
