Re: btrfs fail behavior when a device vanishes

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Dec 31, 2015 at 01:11:25PM -0700, Chris Murphy wrote:
> 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?

   I'm guessing completely here, but maybe it's trying to write
corrected data to sdc1, because the original read failed?

   Hugo.

> 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.
> 
> 

-- 
Hugo Mills             | Well, sir, the floor is yours. But remember, the
hugo@... carfax.org.uk | roof is ours!
http://carfax.org.uk/  |
PGP: E2AB1DE4          |                                             The Goons

Attachment: signature.asc
Description: Digital signature


[Index of Archives]     [Linux Filesystem Development]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux