From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Steigerwald Subject: btrfs: failed to load free space cache for block group on =?iso-8859-1?q?rsync=B4ing_to_space=5Fcache_BTRFS_with?= subvolume Date: Thu, 23 Jun 2011 19:37:12 +0200 Message-ID: <201106231937.12848.Martin@lichtvoll.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 To: linux-btrfs@vger.kernel.org Return-path: List-ID: Hi! Short summary: I suspect that rsync=B4ing files to a newly created BTRF= S=20 partition with a subvolume *and* enabled space_cache triggers the error= =20 mentioned in the subject line of this mail. I reported this also as: Bug 38112 - btrfs: failed to load free space cache for block group on=20 rsync=B4ing to space_cache BTRFS with subvolume https://bugzilla.kernel.org/show_bug.cgi?id=3D38112 I will add a reference to my post here to the bug report, so feel free = to=20 use whatever suits you best to follow up. This happened on a ThinkPad T520 with 3.0.0-rc3-amd64 Debian/GNU Linux=20 kernel. The issue happened on a 2.5 inch external eSATA/USB harddisk wh= ich=20 I changed to BTRFS. On the repoot after the rsync process was stalled t= he=20 unrelated non space cache using root filesystem did not mount anymore w= ith=20 3.0.0-rc3-amd64 and 2.6.39-2-amd64 kernel. But thankfully it did mount=20 with a 2.6.38 grml 2011 amd64 kernel and now work again. Thus I did merkaba:~> mkfs.btrfs -L daten /dev/sdc2 WARNING! - Btrfs Btrfs v0.19 IS EXPERIMENTAL WARNING! - see http://btrfs.wiki.kernel.org before using fs created label daten on /dev/sdc2 nodesize 4096 leafsize 4096 sectorsize 4096 size 447.13GB Btrfs Btrfs v0.19 merkaba:~> mount -o space_cache,compress=3Dlzo /dev/sdc2 /mnt/amazon-da= ten=20 merkaba:~> dmesg | tail -3 [137440.930038] device label daten devid 1 transid 7 /dev/sdc2 [137440.930507] btrfs: enabling disk space caching [137440.930518] btrfs: use lzo compression Then I unmounted, added a fstab entry without space_cache option since = I=20 read that once BTRFS created a space_cache it would use it anyway it is= =20 mounted with clear_cache to clear the cache again. I created a sub volume for movies, cause I wanted to be able to not=20 snapshot the movie files: merkaba:~> btrfs subvolume create /mnt/amazon-daten/Filme Create subvolume '/mnt/amazon-daten/Filme' I then did my rsync from the backup which BTW was a BTRFS with space_ca= che=20 as well - created today: merkaba:~> rsync -a -H --acls --xattrs --sparse /mnt/steigerwald-daten/= =20 /mnt/amazon-daten A short while after starting the rsync I got: 137927.147255] btrfs: failed to load free space cache for block group=20 147131990016 [138110.390962] ------------[ cut here ]------------ [138110.392736] kernel BUG at=20 /media/data/mattems/src/linux-2.6-3.0.0~rc3/debian/build/source_amd64_n= one/fs/btrfs/free- space-cache.c:1186! [138110.394536] invalid opcode: 0000 [#1] SMP=20 [138110.396322] CPU 0=20 [138110.396331] Modules linked in: ufs qnx4 hfsplus hfs minix ntfs vfat= =20 msdos fat jfs xfs reiserfs ext3 jbd ext2 ums_cypress usb_storage uas tu= n=20 cpufreq_conservative cpufreq_stats parport_pc ppdev cpufreq_powersave=20 cpufreq_userspace lp parport bnep acpi_cpufreq mperf rfcomm bluetooth=20 uinput fuse nfsd nfs lockd fscache auth_rpcgss nfs_acl sunrpc ext4 mbca= che=20 jbd2 crc16 acpiphp pci_hotplug loop firewire_sbp2 snd_hda_codec_hdmi=20 snd_hda_codec_conexant joydev arc4 snd_hda_intel snd_hda_codec snd_hwde= p=20 ac snd_pcm snd_seq snd_timer snd_seq_device thinkpad_acpi tpm_tis snd=20 nvram psmouse tpm battery evdev serio_raw i2c_i801 pcspkr tpm_bios=20 power_supply i915 wmi drm_kms_helper soundcore snd_page_alloc rfkill dr= m=20 i2c_algo_bit i2c_core video button processor dm_mod raid10 raid456=20 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx= =20 raid1 raid0 multipath linear md_mod btrfs zlib_deflate crc32c libcrc32c= sg=20 sr_mod sd_mod cdrom crc_t10dif usbhid sdhci_pci firewire_ohci sdhci hid= =20 mmc_core ahci sata_sil24 libahci libata firewire_core crc_itu_t scsi_mo= d=20 ehci_hcd thermal thermal_sys usbcore e1000e [last unloaded: cfg80211] [138110.407957]=20 [138110.409950] Pid: 26438, comm: btrfs-transacti Tainted: G W = =20 3.0.0-rc3-amd64 #1 LENOVO 42433WG/42433WG [138110.411984] RIP: 0010:[] []=20 recalculate_thresholds+0x21/0x6c [btrfs] [138110.414051] RSP: 0018:ffff880182b2fcd8 EFLAGS: 00010202 [138110.416107] RAX: 0000000000000001 RBX: ffff880212442440 RCX:=20 0000000008000000 [138110.418179] RDX: 0000000007ffffff RSI: 0000000000000002 RDI:=20 ffff880212442440 [138110.420244] RBP: 0000000000000000 R08: 0000000008000000 R09:=20 ffff88019a155720 [138110.422297] R10: ffff880105f6e3b8 R11: ffff880100000001 R12:=20 ffff88020f220ba0 [138110.424356] R13: 0000002241fdd000 R14: ffff880105f6e3b8 R15:=20 0000000000001000 [138110.426410] FS: 0000000000000000(0000) GS:ffff88021e200000(0000)=20 knlGS:0000000000000000 [138110.428467] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [138110.430522] CR2: 00007f0529281034 CR3: 0000000146086000 CR4:=20 00000000000406f0 [138110.432576] DR0: 0000000000000000 DR1: 0000000000000000 DR2:=20 0000000000000000 [138110.434620] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:=20 0000000000000400 [138110.436656] Process btrfs-transacti (pid: 26438, threadinfo=20 ffff880182b2e000, task ffff880212054140) [138110.438704] Stack: [138110.440740] ffffffffa01baa5e ffff880105f6e390 ffff8802092f7c80=20 0000000005f6c0b8 [138110.442788] ffff8802092f7d58 0000000000000001 ffff8802092f7c80=20 0000000000001000 [138110.444814] 0000002241fdd000 0000002241fddfff 0000002241fde000=20 ffff880105f6c000 [138110.446836] Call Trace: [138110.448914] [] ? __btrfs_add_free_space+0x1fc/0x= 2f4=20 [btrfs] [138110.450923] [] ? unpin_extent_range+0x95/0x131 [= btrfs] [138110.452917] [] ? btrfs_finish_extent_commit+0xab= /0x19f=20 [btrfs] [138110.454902] [] ? btrfs_commit_transaction+0x566/= 0x67e=20 [btrfs] [138110.456874] [] ? wake_up_bit+0x20/0x20 [138110.458838] [] ? start_transaction+0x1f5/0x242 [= btrfs] [138110.460786] [] ? transaction_kthread+0x173/0x22d= =20 [btrfs] [138110.462733] [] ? find_and_setup_root+0xcb/0xcb [= btrfs] [138110.464658] [] ? find_and_setup_root+0xcb/0xcb [= btrfs] [138110.466541] [] ? kthread+0x7a/0x82 [138110.468411] [] ? kernel_thread_helper+0x4/0x10 [138110.470274] [] ? kthread_worker_fn+0x147/0x147 [138110.472111] [] ? gs_change+0x13/0x13 [138110.473928] Code: 30 48 c7 47 20 00 00 00 00 c3 48 8b 47 38 31 d2 8= b=20 77 20 4c 8b 40 70 48 8b 48 09 49 c1 e0 0f 49 8d 44 08 ff 49 f7 f0 39 c6= 7e=20 04 <0f> 0b eb fe 48 81 f9 ff ff ff 3f b8 00 80 00 00 76 0b 48 89 c8=20 [138110.475922] RIP [] recalculate_thresholds+0x21/0= x6c=20 [btrfs] [138110.477847] RSP [138110.549460] ---[ end trace 131766a12388cd20 ]--- [138138.490877] BUG: soft lockup - CPU#2 stuck for 22s! [btrfs-delayed- m:26480] [138138.490885] Modules linked in: ufs qnx4 hfsplus hfs minix ntfs vfat= =20 msdos fat jfs xfs reiserfs ext3 jbd ext2 ums_cypress usb_storage uas tu= n=20 cpufreq_conservative cpufreq_stats parport_pc ppdev cpufreq_powersave=20 cpufreq_userspace lp parport bnep acpi_cpufreq mperf rfcomm bluetooth=20 uinput fuse nfsd nfs lockd fscache auth_rpcgss nfs_acl sunrpc ext4 mbca= che=20 jbd2 crc16 acpiphp pci_hotplug loop firewire_sbp2 snd_hda_codec_hdmi=20 snd_hda_codec_conexant joydev arc4 snd_hda_intel snd_hda_codec snd_hwde= p=20 ac snd_pcm snd_seq snd_timer snd_seq_device thinkpad_acpi tpm_tis snd=20 nvram psmouse tpm battery evdev serio_raw i2c_i801 pcspkr tpm_bios=20 power_supply i915 wmi drm_kms_helper soundcore snd_page_alloc rfkill dr= m=20 i2c_algo_bit i2c_core video button processor dm_mod raid10 raid456=20 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx= =20 raid1 raid0 multipath linear md_mod btrfs zlib_deflate crc32c libcrc32c= sg=20 sr_mod sd_mod cdrom crc_t10dif usbhid sdhci_pci firewire_ohci sdhci hid= =20 mmc_core ahci sata_sil24 libahci libata firewire_core crc_itu_t scsi_mo= d=20 ehci_hcd thermal thermal_sys usbcore e1000e [last unloaded: cfg80211] [138138.491076] CPU 2=20 [138138.491079] Modules linked in: ufs qnx4 hfsplus hfs minix ntfs vfat= =20 msdos fat jfs xfs reiserfs ext3 jbd ext2 ums_cypress usb_storage uas tu= n=20 cpufreq_conservative cpufreq_stats parport_pc ppdev cpufreq_powersave=20 cpufreq_userspace lp parport bnep acpi_cpufreq mperf rfcomm bluetooth=20 uinput fuse nfsd nfs lockd fscache auth_rpcgss nfs_acl sunrpc ext4 mbca= che=20 jbd2 crc16 acpiphp pci_hotplug loop firewire_sbp2 snd_hda_codec_hdmi=20 snd_hda_codec_conexant joydev arc4 snd_hda_intel snd_hda_codec snd_hwde= p=20 ac snd_pcm snd_seq snd_timer snd_seq_device thinkpad_acpi tpm_tis snd=20 nvram psmouse tpm battery evdev serio_raw i2c_i801 pcspkr tpm_bios=20 power_supply i915 wmi drm_kms_helper soundcore snd_page_alloc rfkill dr= m=20 i2c_algo_bit i2c_core video button processor dm_mod raid10 raid456=20 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx= =20 raid1 raid0 multipath linear md_mod btrfs zlib_deflate crc32c libcrc32c= sg=20 sr_mod sd_mod cdrom crc_t10dif usbhid sdhci_pci firewire_ohci sdhci hid= =20 mmc_core ahci sata_sil24 libahci libata firewire_core crc_itu_t scsi_mo= d=20 ehci_hcd thermal thermal_sys usbcore e1000e [last unloaded: cfg80211] [138138.491241]=20 [138138.491248] Pid: 26480, comm: btrfs-delayed-m Tainted: G D W = =20 3.0.0-rc3-amd64 #1 LENOVO 42433WG/42433WG [138138.491258] RIP: 0010:[] []=20 _raw_spin_lock+0x13/0x1b [138138.491276] RSP: 0018:ffff8801011ff958 EFLAGS: 00000297 [138138.491282] RAX: 000000000000143d RBX: ffff88019576cc28 RCX:=20 0000000000001000 [138138.491288] RDX: 000000000000143c RSI: ffff8802092f7c80 RDI:=20 ffff880212442440 [138138.491294] RBP: ffff880105f6e390 R08: 0000002241c8c000 R09: ffffff= ffffffffff [138138.491299] R10: dead000000200200 R11: 0000000000000000 R12:=20 ffffffff8133d5ce [138138.491305] R13: 0000000000000000 R14: 0000000000000af7 R15:=20 ffffffffa01a4f88 [138138.491312] FS: 0000000000000000(0000) GS:ffff88021e280000(0000)=20 knlGS:0000000000000000 [138138.491318] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [138138.491324] CR2: 00007f9be3bed000 CR3: 0000000001603000 CR4:=20 00000000000406e0 [138138.491329] DR0: 0000000000000000 DR1: 0000000000000000 DR2:=20 0000000000000000 [138138.491335] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:=20 0000000000000400 [138138.491342] Process btrfs-delayed-m (pid: 26480, threadinfo=20 ffff8801011fe000, task ffff8801c2b3d120) [138138.491347] Stack: [138138.491351] ffffffffa017fbcc ffff880189996b40 ffff880100000021=20 0000000000000000 [138138.491361] 0000000000001000 0000000003856f00 ffffffffa01a4300=20 ffff880105f6e394 [138138.491371] 0000000000000000 0000002241c8c000 00010000a01a4300=20 ffff880138b41800 [138138.491382] Call Trace: [138138.491419] [] ? find_free_extent+0x542/0xa4b [b= trfs] [138138.491456] [] ? map_private_extent_buffer+0xa3/= 0xc4=20 [btrfs] [138138.491489] [] ? btrfs_reserve_extent+0xbc/0x1cd= =20 [btrfs] [138138.491518] [] ? reserve_metadata_bytes+0x54/0x1= a6=20 [btrfs] [138138.491548] [] ? btrfs_alloc_free_block+0x161/0x= 292=20 [btrfs] [138138.491575] [] ? __btrfs_cow_block+0x109/0x34b [= btrfs] [138138.491586] [] ? check_preempt_wakeup+0x11f/0x19= f [138138.491612] [] ? btrfs_cow_block+0xf7/0x143 [btr= fs] [138138.491639] [] ? btrfs_search_slot+0x140/0x4c6 [= btrfs] [138138.491647] [] ? __switch_to+0xc5/0x288 [138138.491654] [] ? pick_next_task_fair+0xf9/0x10b [138138.491664] [] ? mutex_lock+0xd/0x2c [138138.491695] [] ? btrfs_lookup_inode+0x25/0x84 [b= trfs] [138138.491704] [] ? mutex_lock+0xd/0x2c [138138.491733] [] ? btrfs_update_delayed_inode+0x6b= /0x126=20 [btrfs] [138138.491767] [] ? start_transaction+0x1f5/0x242 [= btrfs] [138138.491795] [] ?=20 btrfs_async_run_delayed_node_done+0x8a/0x138 [btrfs] [138138.491828] [] ? worker_loop+0x186/0x4a1 [btrfs] [138138.491837] [] ? schedule+0x5ed/0x61a [138138.491866] [] ? btrfs_queue_worker+0x24a/0x24a = [btrfs] [138138.491894] [] ? btrfs_queue_worker+0x24a/0x24a = [btrfs] [138138.491904] [] ? kthread+0x7a/0x82 [138138.491914] [] ? kernel_thread_helper+0x4/0x10 [138138.491923] [] ? kthread_worker_fn+0x147/0x147 [138138.491932] [] ? gs_change+0x13/0x13 [138138.491936] Code: 00 01 00 75 04 f0 0f b1 17 0f 94 c2 0f b6 c2 85 c= 0=20 0f 95 c0 0f b6 c0 c3 b8 00 00 01 00 f0 0f c1 07 0f b7 d0 c1 e8 10 39 c2= 74=20 07 90 0f b7 17 eb f5 c3 9c 58 66 66 90 66 90 48 89 c2 fa 66 66=20 [138138.492000] Call Trace: [138138.492029] [] ? find_free_extent+0x542/0xa4b [b= trfs] [138138.492062] [] ? map_private_extent_buffer+0xa3/= 0xc4=20 [btrfs] [138138.492092] [] ? btrfs_reserve_extent+0xbc/0x1cd= =20 [btrfs] [138138.492121] [] ? reserve_metadata_bytes+0x54/0x1= a6=20 [btrfs] [138138.492150] [] ? btrfs_alloc_free_block+0x161/0x= 292=20 [btrfs] [138138.492176] [] ? __btrfs_cow_block+0x109/0x34b [= btrfs] [138138.492185] [] ? check_preempt_wakeup+0x11f/0x19= f [138138.492211] [] ? btrfs_cow_block+0xf7/0x143 [btr= fs] [138138.492238] [] ? btrfs_search_slot+0x140/0x4c6 [= btrfs] [138138.492245] [] ? __switch_to+0xc5/0x288 [138138.492251] [] ? pick_next_task_fair+0xf9/0x10b [138138.492260] [] ? mutex_lock+0xd/0x2c [138138.492289] [] ? btrfs_lookup_inode+0x25/0x84 [b= trfs] [138138.492298] [] ? mutex_lock+0xd/0x2c [138138.492326] [] ? btrfs_update_delayed_inode+0x6b= /0x126=20 [btrfs] [138138.492359] [] ? start_transaction+0x1f5/0x242 [= btrfs] [138138.492387] [] ?=20 btrfs_async_run_delayed_node_done+0x8a/0x138 [btrfs] [138138.492417] [] ? worker_loop+0x186/0x4a1 [btrfs] [138138.492426] [] ? schedule+0x5ed/0x61a [138138.492453] [] ? btrfs_queue_worker+0x24a/0x24a = [btrfs] [138138.492480] [] ? btrfs_queue_worker+0x24a/0x24a = [btrfs] [138138.492489] [] ? kthread+0x7a/0x82 [138138.492498] [] ? kernel_thread_helper+0x4/0x10 [138138.492507] [] ? kthread_worker_fn+0x147/0x147 [138138.492516] [] ? gs_change+0x13/0x13 merkaba:~>=20 Message from syslogd@merkaba at Jun 23 18:30:41 ... kernel:[138166.427817] Stack: Message from syslogd@merkaba at Jun 23 18:30:41 ... kernel:[138166.427851] Call Trace: Message from syslogd@merkaba at Jun 23 18:30:41 ... kernel:[138166.428406] Code: 00 01 00 75 04 f0 0f b1 17 0f 94 c2 0f b6= c2=20 85 c0 0f 95 c0 0f b6 c0 c3 b8 00 00 01 00 f0 0f c1 07 0f b7 d0 c1 e8 10= 39=20 c2 74 07 90 0f b7 17 eb f5 c3 9c 58 66 66 90 66 90 48 89 c2 fa 66 = 66=20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396102] Stack: Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396150] Call Trace: Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396227] Code: e0 ff ff a8 08 75 0e e8 7e ba da e0 66 90= fa=20 66 66 90 66 66 90 65 48 8b 04 25 08 cd 00 00 83 88 3c e0 ff ff 04 eb 0c= 8b=20 57 04 ec=20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396667] Stack: Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396700] Call Trace: Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396703] =20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.396840] =20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.397396] Code: 41 ff c0 4c 89 0c 07 48 83 c0 08 41 39 c8= 7c=20 e8 c3 48 63 c9 45 31 c0 45 31 c9 48 83 c1 3f 45 31 d2 48 c1 e9 06 eb 19= 4a=20 8b 04 02=20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.398412] Stack: Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.398447] Call Trace: Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.398451] =20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.398485] =20 Message from syslogd@merkaba at Jun 23 18:30:46 ... kernel:[138171.398574] Code: 44 e0 ff ff 00 00 01 00 48 63 80 44 e0 ff= ff a9=20 00 ff ff 07 75 37 65 8b 04 25 80 26 01 00 85 c0 74 2b 80 3d 2d a2 63 00= 00=20 75 07 4e f4 fb ff eb 1b 65 48 8b 3c 25 70 e6 00 00 48 85 ff 74 0d=20 Since the backup process was stalled, rsync was D+ and umount -lf did=20 hang, too. I decided that it would be better to reboot my machine. Then I was scared away that neither 3.0.0-rc3-amd64 and 2.6.39-2-amd64=20 debian kernel were able to mount a completely unrelated BTRFS filesyste= m.=20 Namely my BTRFS root filesystem located on an Intel SSD 320 with 300 GB= =2E I=20 got a backtrace I unfortunately did not photograph, cause I thought I w= ill=20 see it on recovery with GRML anyway, and got dumped to initramfs shell. On an other ThinkPad, a T42, I grabbed grml 2011.05 64-Bit and dd=B4d i= t a=20 an USB stick. And thanks God there, with a 2.6.38 grml kernel, my BTRFS= =20 root filesystem did mount well. Just for sure I run a mount -o clear_ca= che=20 on the root filesystem although I never activated space_cache there. Then I rebooted into my Debian Unstable and all was well again. The only hints in syslog I found were: 1741 Jun 23 18:15:34 merkaba kernel: [137261.752879] ata6: SATA link up= =20 3.0 Gbps (SStatus 123 SControl 300) 1742 Jun 23 18:15:34 merkaba kernel: [137261.753946] ata6.00: ACPI cmd=20 ef/02:00:00:00:00:a0 (SET FEATURES) succeeded 1743 Jun 23 18:15:34 merkaba kernel: [137261.753956] ata6.00: ACPI cmd=20 f5/00:00:00:00:00:a0 (SECURITY FREEZE LOCK) filtered out 1744 Jun 23 18:15:34 merkaba kernel: [137261.756041] ata6.00: ACPI cmd=20 ef/02:00:00:00:00:a0 (SET FEATURES) succeeded 1745 Jun 23 18:15:34 merkaba kernel: [137261.756055] ata6.00: ACPI cmd=20 f5/00:00:00:00:00:a0 (SECURITY FREEZE LOCK) filtered out 1746 Jun 23 18:15:34 merkaba kernel: [137261.757703] ata6.00: configure= d=20 for UDMA/133 1747 Jun 23 18:15:34 merkaba kernel: [137261.772834] ata6: EH complete 1748 Jun 23 18:17:01 merkaba /USR/SBIN/CRON[25888]: (root) CMD ( cd /= &&=20 run-parts --report /etc/cron.hourly) 1749 Jun 23 18:18:34 merkaba kernel: [137440.930038] device label daten= =20 devid 1 transid 7 /dev/sdc2 1750 Jun 23 18:18:34 merkaba kernel: [137440.930507] btrfs: enabling di= sk=20 space caching 1751 Jun 23 18:18:34 merkaba kernel: [137440.930518] btrfs: use lzo=20 compression 1752 Jun 23 18:22:00 merkaba kernel: [137646.534245] device label daten= =20 devid 1 transid 10 /dev/sdc2 1753 Jun 23 18:22:00 merkaba kernel: [137646.534556] btrfs: use lzo=20 compression 1754 Jun 23 18:22:00 merkaba kernel: [137646.549740] btrfs: disk space=20 caching is enabled 1755 Jun 23 18:24:48 merkaba kernel: [137813.653916] device label daten= - backup devid 1 transid 162 /dev/mapper/steigerwald-daten 1756 Jun 23 18:24:48 merkaba kernel: [137813.654566] btrfs: use lzo=20 compression 1757 Jun 23 18:24:48 merkaba kernel: [137813.691677] btrfs: disk space=20 caching is enabled 1758 Jun 23 18:26:41 merkaba kernel: [137927.147252] block group=20 147131990016 has an wrong amount of free space 1759 Jun 23 18:26:41 merkaba kernel: [137927.147255] btrfs: failed to l= oad=20 free space cache for block group 147131990016 Then there is a long gap where apparently nothing got written onto the=20 root filesystem anymore. Partly due to me using GRML trying to restore=20 things. 1760 Jun 23 19:00:01 merkaba kernel: imklog 5.8.2, log source =3D /proc= /kmsg=20 started. 1761 Jun 23 19:00:01 merkaba rsyslogd: [origin software=3D"rsyslogd"=20 swVersion=3D"5.8.2" x-pid=3D"1342" x-info=3D"http://www.rsyslog.com"] s= tart 1762 Jun 23 19:00:01 merkaba kernel: [ 0.000000] Initializing cgroup= =20 subsys cpuset 1763 Jun 23 19:00:01 merkaba kernel: [ 0.000000] Initializing cgroup= =20 subsys cpu 1764 Jun 23 19:00:01 merkaba kernel: [ 0.000000] Linux version 3.0.0= - rc3-amd64 (Debian 3.0.0~rc3-1~experimental.1) (maks@debian.org) ( g= cc=20 version 4.4.6 (Debian 4.4.6-6) ) #1 SMP Thu Jun 16 13:23:22 UTC 2011 Since rsyncing files and movies to two different BTRFS partitions that=20 actually used space_cache I suspect that the failure is related to havi= ng=20 the subvolume on the BTRFS filesystem that failed so miserably. As for reproducability: I am now restoring the backup for my external=20 drive to a BTRFS *without* space cache to have my data redundant again.= =20 But I did create the subvolume again to see whether the only difference= =20 really is the space cache. Lets see how it turns out. Thus I do not like to use this drive for another experiment. But I shou= ld=20 have another 60/80 GB 2.5 inch drives here where I could test it.=20 Suspected steps to reproduce: - create BTRFS - mount with compress=3Dlzo,space_cache enabled - umount - mount again only with compress=3Dlzo - create subvolume - rsync stuff to it - issue should appear after some MB of data transferred Ciao, --=20 Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html