| Message ID | npds64$nu3$1@blaine.gmane.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Le 21/08/2016 à 17:39, Jean-Denis Girard a écrit : > Hi list, > > After upgrading my Fedora 23 system from 4.4.12 to 4.7.2, I'm seeing one > btrfs-cleaner process stuck at 100% CPU. The problem disappears when > going back to 4.4 kernel (4.4.17), but is also present with Fedora > kernel 4.6.6-200.fc23. Just for the archives, I found that the problem was related to fragmentation. Mounting without autodefrag on 4.7.2 avoided btrfs-cleaner stuck at 100 % CPU. Then I did manually defragment all Btrfs volumes, and could then remount with autodefrag. Every thing is ok after ~12 hours uptime. Thanks,
diff -Naur linux-4.4.6.ORIG/fs/btrfs/ctree.c linux-4.4.6/fs/btrfs/ctree.c --- linux-4.4.6.ORIG/fs/btrfs/ctree.c 2016-01-10 13:01:32.000000000 -1000 +++ linux-4.4.6/fs/btrfs/ctree.c 2016-03-30 06:19:16.397973820 -1000 @@ -20,6 +20,7 @@ #include <linux/slab.h> #include <linux/rbtree.h> #include "ctree.h" +#include <linux/vmalloc.h> #include "disk-io.h" #include "transaction.h" #include "print-tree.h" @@ -5362,10 +5363,13 @@ goto out; } - tmp_buf = kmalloc(left_root->nodesize, GFP_NOFS); + tmp_buf = kmalloc(left_root->nodesize, GFP_KERNEL | __GFP_NOWARN); if (!tmp_buf) { - ret = -ENOMEM; - goto out; + tmp_buf = vmalloc(left_root->nodesize); + if (!tmp_buf) { + ret = -ENOMEM; + goto out; + } } left_path->search_commit_root = 1; @@ -5566,7 +5570,7 @@ out: btrfs_free_path(left_path); btrfs_free_path(right_path); - kfree(tmp_buf); + kvfree(tmp_buf); return ret; }
Hi list, After upgrading my Fedora 23 system from 4.4.12 to 4.7.2, I'm seeing one btrfs-cleaner process stuck at 100% CPU. The problem disappears when going back to 4.4 kernel (4.4.17), but is also present with Fedora kernel 4.6.6-200.fc23. 4.4.12 and 4.4.17 are built from source, with 2 patches (see attached). 4.7.2 is built from source without any patch. Main Btrfs is RAID1 on 2 disks behind bcache, with 13 sub-volumes, and less than 300 snapshots (more details below). There are 2 other Btrfs used for backup, so not mounted when the problem appears. The btrfs-cleaner jumps at 100% after about ~15 min uptime. I let it run about ~18 hours, btrfs-cleaner stayed at 100%. Unmounting all the sub-volumes clears the problem. There is no error in the logs, all the sub-volumes are mounted ok, I can use the system. I did a scrub and balance, which finished without any error. I'm back on 4.4.17 now, but what can I do to debug this problem ? [jdg@tiare ~]$ sudo btrfs fi sh Label: none uuid: c5b8386b-b81d-4473-9340-7b8a74fc3a3c Total devices 2 FS bytes used 1.04TiB devid 1 size 1.82TiB used 1.08TiB path /dev/bcache0 devid 2 size 1.82TiB used 1.08TiB path /dev/bcache1 Label: none uuid: e86cf0f5-ae16-408c-a4f8-19727aa2a3d4 Total devices 1 FS bytes used 191.20GiB devid 1 size 279.46GiB used 240.06GiB path /dev/sdd Label: none uuid: d0d09c79-42d7-4958-bccb-480eb27aec38 Total devices 1 FS bytes used 611.38GiB devid 1 size 931.51GiB used 620.07GiB path /dev/sde [jdg@tiare ~]$ sudo btrfs fi usage /home/jdg/ Overall: Device size: 3.64TiB Device allocated: 2.16TiB Device unallocated: 1.48TiB Device missing: 0.00B Used: 2.08TiB Free (estimated): 798.35GiB (min: 798.35GiB) Data ratio: 2.00 Metadata ratio: 2.00 Global reserve: 512.00MiB (used: 0.00B) Data,RAID1: Size:1.08TiB, Used:1.04TiB /dev/bcache0 1.08TiB /dev/bcache1 1.08TiB Metadata,RAID1: Size:4.00GiB, Used:2.74GiB /dev/bcache0 4.00GiB /dev/bcache1 4.00GiB System,RAID1: Size:32.00MiB, Used:256.00KiB /dev/bcache0 32.00MiB /dev/bcache1 32.00MiB Unallocated: /dev/bcache0 757.99GiB /dev/bcache1 757.99GiB [jdg@tiare ~]$ mount -t btrfs /dev/bcache0 on /var/lib/pgsql type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1131,subvol=/pgsql) /dev/bcache0 on /home/SysNux type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1062,subvol=/SysNux) /dev/bcache0 on /home/Vidéos type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1281,subvol=/Vidéos) /dev/bcache0 on /var/lib/libvirt/images type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1136,subvol=/images-vm) /dev/bcache0 on /mnt/snapshots type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1292,subvol=/Snapshots) /dev/bcache0 on /home/Photos type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=676,subvol=/Photos) /dev/bcache0 on /home/vaiana type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1076,subvol=/vaiana) /dev/bcache0 on /home/Films type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=258,subvol=/Films) /dev/bcache0 on /home/Partage type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1059,subvol=/Partage) /dev/bcache0 on /home/jdg type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1073,subvol=/jdg) /dev/bcache0 on /home/michael type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1075,subvol=/michael) /dev/bcache0 on /home/cathy type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=1074,subvol=/cathy) /dev/bcache0 on /home/Musique type btrfs (rw,noatime,nodiratime,seclabel,compress=zlib,ssd,space_cache,autodefrag,skip_balance,subvolid=961,subvol=/Musique) Thanks,