From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ble59-2-81-56-123-40.fbx.proxad.net ([81.56.123.40]:36939 "EHLO jmuchemb.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750790AbaKKUSx (ORCPT ); Tue, 11 Nov 2014 15:18:53 -0500 Received: from [10.236.3.1] (tecra [10.236.3.1]) by jmuchemb.eu (Postfix) with ESMTP id 79A0C46A6D for ; Tue, 11 Nov 2014 21:10:14 +0100 (CET) Message-ID: <54626D23.20701@jmuchemb.eu> Date: Tue, 11 Nov 2014 21:10:11 +0100 From: Julien Muchembled MIME-Version: 1.0 To: linux-btrfs@vger.kernel.org Subject: kernel >= 3.16 saturates I/O endlessly and without reason Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="NH1Gb8WkGNRicIRB4onElRwIKof80fjD0" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --NH1Gb8WkGNRicIRB4onElRwIKof80fjD0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hello, I upgraded my kernel from 3.15.10 to 3.17.2 and after a while, btrfs kwor= kers started to read/write data at maximum speed for hours whereas I was = doing nothing. So I rebooted with kernel 3.15.10 and hopefully everything= went back to normal. Later attempts to upgrade to 3.16.7 or 3.17.2 showe= d the same issue, immediately at boot or after a while. In order to investigate a little, I copied the partition and mounted it i= n qemu (snapshot mode, with cow file in tmpfs, debian kernel 3.16.7-2). I= could see that btrfs always wrote the same ~8MB in loop. qemu used all c= pu and when I stopped it, it wrote 190G and the generation number raised = from 625955 to 853922. I dumped the FS with btrfs-image. The restored FS has the same issue so I= can send the image (78M) to anyone who would like to debug. $ btrfs fi df / Data, single: total=3D13.62GiB, used=3D12.60GiB System, single: total=3D4.00MiB, used=3D16.00KiB Metadata, single: total=3D1.00GiB, used=3D747.48MiB GlobalReserve, single: total=3D256.00MiB, used=3D0.00B $ btrfs fi show --mounted Label: none uuid: f5a13768-b968-49c7-8a09-fdad88b83ea8 Total devices 1 FS bytes used 13.33GiB devid 1 size 14.62GiB used 14.62GiB path /dev/sdb2 $ btrfs sub list -a / ID 257 gen 626025 top level 5 path /@ ID 269 gen 28 top level 257 path @/usr/src/linux-sysrcd ID 278 gen 599690 top level 257 path @/usr/src/linux-3.15-1 ID 279 gen 13003 top level 257 path @/usr/src/python3.3 ID 281 gen 13036 top level 257 path @/usr/src/python3.4 ID 282 gen 614068 top level 257 path @/usr/src/linux-3.16-1 ID 283 gen 599642 top level 257 path @/usr/src/linux-3.17-1 --NH1Gb8WkGNRicIRB4onElRwIKof80fjD0 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCAAGBQJUYm0mAAoJEEwjvlkacWMk4q8QAIISldEDF8lbVh2td7MG9V9I tx38s6RKq/ioRzePJullc/6WL9HKQRXn8X1U53Rr6NUkbvDY8OHGA/EVooXdN+5A 8QIVfV5FF11LnJ0opBkH9xLuh1VXe6RhsKTVebQdOtNyIE03+eUkaIEGU4sQvVXy x8eC/MUqlWk35XorkeooYzgSeCJ3klCrg6J+RC4CjbzVLHimTdO4QbXzWCI0NHw0 bY8a8D+iD/I1DVxpkDnx7PyrRmq4h0Y0p6WRkAxj/GcFce1ytnCgEY2wYCsCCl3D vhtwjRHsCaeyS1ipPHVmjTF+KxxTukNK/xQvoIvtpE2qbAeSP3Ar4mE585u/+zkr Wa/VYgeDGooZfMgEvCRF8L3NTaAzP9tyGJ4LziB4/iEXWpa8DTGaVWQjBoSqg9Wz aE/GglDtmzmmEGD2LNR/zz6EffjM6Xxafe+UkIWk91/QEH8Vr+II4y2qx3fRL+Dh AhixK3L9GvbLKPBTsqOQN3B70D/eMRbAAp3HqNcARdiZ8RHqzEJGfRFvsAy9+99Y ZJbG/nqTWdTj/f8RCY/N5fLIS+w+lavkS/jLxk3Hy2uMQdLn9F8nhOgkN3zn0fAa th0Qd79/ueVyr1Xli4tL0Z6nkTSrFUvpUqhzIFG4TzepX9dz5r8dkEmwdUUGSrbC ORiN3xbTjpne3hwHt3oR =jLfE -----END PGP SIGNATURE----- --NH1Gb8WkGNRicIRB4onElRwIKof80fjD0--