Hello, I''m running Ubuntu under KVM, with btrfs on the host where the Qemu/KVM image is stored, the VM was also running at the time. I was going to check something unrelated in the dmesg output, as I did that I noticed some errors in it about btrfs here they are: [ 4294.431807] btrfs: block rsv returned -28 [ 4294.431811] ------------[ cut here ]------------ [ 4294.431831] WARNING: at fs/btrfs/extent-tree.c:5985 btrfs_alloc_free_block+0x344/0x350 [btrfs]() [ 4294.431835] Modules linked in: xfs exportfs jfs kvm_intel kvm fuse btrfs zlib_deflate crc32c libcrc32c ext4 jbd2 mbcache crc16 snd_hda_codec_realtek rc_dib0700_rc5 mt2266 ir_lirc_codec lirc_dev ir_mce_kbd_decoder ir_sony_decoder ir_jvc_decoder dvb_usb_dib0700 ir_rc6_decoder dib3000mc dib8000 dib0070 dib7000m dib0090 dib7000p dibx000_common ir_rc5_decoder ir_nec_decoder usb_storage uas dvb_usb dvb_core rc_core joydev snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_timer ppdev parport_pc nvidia(P) snd soundcore i2c_i801 serio_raw evdev parport floppy 8139too 8139cp iTCO_wdt i7core_edac edac_core pcspkr button processor i2c_core iTCO_vendor_support mii reiserfs aes_x86_64 cryptd aes_generic xts gf128mul dm_crypt dm_mod usbhid hid sd_mod sr_mod pata_jmicron cdrom ahci libahci ata_piix uhci_hcd pata_acpi libata scsi_mod ehci_hcd usbcore usb_common [ 4294.431967] Pid: 10505, comm: btrfs-endio-wri Tainted: P O 3.2.7-1-ARCH #1 [ 4294.431969] Call Trace: [ 4294.431974] [<ffffffff8106609f>] warn_slowpath_common+0x7f/0xc0 [ 4294.431976] [<ffffffff810660fa>] warn_slowpath_null+0x1a/0x20 [ 4294.431982] [<ffffffffa0f95fd4>] btrfs_alloc_free_block+0x344/0x350 [btrfs] [ 4294.431986] [<ffffffffa0f84e62>] __btrfs_cow_block+0x122/0x430 [btrfs] [ 4294.431991] [<ffffffffa0f85266>] btrfs_cow_block+0xf6/0x250 [btrfs] [ 4294.431997] [<ffffffffa0fd42e0>] ? btrfs_set_lock_blocking_rw+0x50/0xb0 [btrfs] [ 4294.432002] [<ffffffffa0f88dde>] btrfs_search_slot+0x18e/0x8a0 [btrfs] [ 4294.432007] [<ffffffffa0fe0614>] ? tree_insert+0x84/0x1e0 [btrfs] [ 4294.432013] [<ffffffffa0f9a374>] btrfs_lookup_csum+0x74/0x170 [btrfs] [ 4294.432016] [<ffffffff81152183>] ? kmem_cache_alloc+0x133/0x160 [ 4294.432022] [<ffffffffa0f9b3c4>] btrfs_csum_file_blocks+0xb4/0x680 [btrfs] [ 4294.432029] [<ffffffffa0faaa99>] ? insert_reserved_file_extent.constprop.52+0x219/0x270 [btrfs] [ 4294.432035] [<ffffffffa0fa8f35>] add_pending_csums.isra.38+0x45/0x60 [btrfs] [ 4294.432042] [<ffffffffa0fabdff>] btrfs_endio_direct_write+0x1ff/0x300 [btrfs] [ 4294.432045] [<ffffffff8119bc4d>] bio_endio+0x1d/0x40 [ 4294.432050] [<ffffffffa0f9e736>] end_workqueue_fn+0x56/0x140 [btrfs] [ 4294.432056] [<ffffffffa0fce920>] worker_loop+0x150/0x520 [btrfs] [ 4294.432059] [<ffffffff8104d788>] ? __wake_up_common+0x58/0x90 [ 4294.432065] [<ffffffffa0fce7d0>] ? btrfs_queue_worker+0x300/0x300 [btrfs] [ 4294.432127] [<ffffffff8108842c>] kthread+0x8c/0xa0 [ 4294.432131] [<ffffffff8145f5f4>] kernel_thread_helper+0x4/0x10 [ 4294.432133] [<ffffffff810883a0>] ? kthread_worker_fn+0x190/0x190 [ 4294.432135] [<ffffffff8145f5f0>] ? gs_change+0x13/0x13 [ 4294.432136] ---[ end trace 4afe986ec803a741 ]--- [ 4294.432146] btrfs: block rsv returned -28 [ 4294.432147] ------------[ cut here ]------------ [ 4294.432152] WARNING: at fs/btrfs/extent-tree.c:5985 btrfs_alloc_free_block+0x344/0x350 [btrfs]() [ 4294.432153] Modules linked in: xfs exportfs jfs kvm_intel kvm fuse btrfs zlib_deflate crc32c libcrc32c ext4 jbd2 mbcache crc16 snd_hda_codec_realtek rc_dib0700_rc5 mt2266 ir_lirc_codec lirc_dev ir_mce_kbd_decoder ir_sony_decoder ir_jvc_decoder dvb_usb_dib0700 ir_rc6_decoder dib3000mc dib8000 dib0070 dib7000m dib0090 dib7000p dibx000_common ir_rc5_decoder ir_nec_decoder usb_storage uas dvb_usb dvb_core rc_core joydev snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_timer ppdev parport_pc nvidia(P) snd soundcore i2c_i801 serio_raw evdev parport floppy 8139too 8139cp iTCO_wdt i7core_edac edac_core pcspkr button processor i2c_core iTCO_vendor_support mii reiserfs aes_x86_64 cryptd aes_generic xts gf128mul dm_crypt dm_mod usbhid hid sd_mod sr_mod pata_jmicron cdrom ahci libahci ata_piix uhci_hcd pata_acpi libata scsi_mod ehci_hcd usbcore usb_common [ 4294.432186] Pid: 10505, comm: btrfs-endio-wri Tainted: P W O 3.2.7-1-ARCH #1 [ 4294.432187] Call Trace: [ 4294.432189] [<ffffffff8106609f>] warn_slowpath_common+0x7f/0xc0 [ 4294.432191] [<ffffffff810660fa>] warn_slowpath_null+0x1a/0x20 [ 4294.432196] [<ffffffffa0f95fd4>] btrfs_alloc_free_block+0x344/0x350 [btrfs] [ 4294.432203] [<ffffffffa0fc5fb0>] ? read_extent_buffer+0xb0/0x190 [btrfs] [ 4294.432207] [<ffffffffa0f84e62>] __btrfs_cow_block+0x122/0x430 [btrfs] [ 4294.432212] [<ffffffffa0f85266>] btrfs_cow_block+0xf6/0x250 [btrfs] [ 4294.432217] [<ffffffffa0fd42e0>] ? btrfs_set_lock_blocking_rw+0x50/0xb0 [btrfs] [ 4294.432222] [<ffffffffa0f88dde>] btrfs_search_slot+0x18e/0x8a0 [btrfs] [ 4294.432227] [<ffffffffa0fe0614>] ? tree_insert+0x84/0x1e0 [btrfs] [ 4294.432293] [<ffffffffa0f9a374>] btrfs_lookup_csum+0x74/0x170 [btrfs] [ 4294.432296] [<ffffffff81152183>] ? kmem_cache_alloc+0x133/0x160 [ 4294.432301] [<ffffffffa0f9b3c4>] btrfs_csum_file_blocks+0xb4/0x680 [btrfs] [ 4294.432308] [<ffffffffa0faaa99>] ? insert_reserved_file_extent.constprop.52+0x219/0x270 [btrfs] [ 4294.432315] [<ffffffffa0fa8f35>] add_pending_csums.isra.38+0x45/0x60 [btrfs] [ 4294.432321] [<ffffffffa0fabdff>] btrfs_endio_direct_write+0x1ff/0x300 [btrfs] [ 4294.432324] [<ffffffff8119bc4d>] bio_endio+0x1d/0x40 [ 4294.432329] [<ffffffffa0f9e736>] end_workqueue_fn+0x56/0x140 [btrfs] [ 4294.432335] [<ffffffffa0fce920>] worker_loop+0x150/0x520 [btrfs] [ 4294.432337] [<ffffffff8104d788>] ? __wake_up_common+0x58/0x90 [ 4294.432343] [<ffffffffa0fce7d0>] ? btrfs_queue_worker+0x300/0x300 [btrfs] [ 4294.432345] [<ffffffff8108842c>] kthread+0x8c/0xa0 [ 4294.432347] [<ffffffff8145f5f4>] kernel_thread_helper+0x4/0x10 [ 4294.432349] [<ffffffff810883a0>] ? kthread_worker_fn+0x190/0x190 [ 4294.432351] [<ffffffff8145f5f0>] ? gs_change+0x13/0x13 [ 4294.432353] ---[ end trace 4afe986ec803a742 ]--- This didn''t cause any crashes or related issues, also unrelated (I think?) is that I get very low performance (about 5MBps according to iostat) in a guest under Qemu/KVM. 3.2.7-1-ARCH x86_64 Arch Linux Thanks. -- 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
On Sat, Feb 25, 2012 at 09:14:01AM +1030, Jordan Windsor wrote:> I''m running Ubuntu under KVM, with btrfs on the host where the > Qemu/KVM image is stored, the VM was also running at the time. I was > going to check something unrelated in the dmesg output, as I did that > I noticed some errors in it about btrfs here they are: > > > [ 4294.431807] btrfs: block rsv returned -28 > [ 4294.431811] ------------[ cut here ]------------ > [ 4294.431831] WARNING: at fs/btrfs/extent-tree.c:5985This is a warning and it shows up from time to time, accross recent releases.> This didn''t cause any crashes or related issues, also unrelated (I > think?) is that I get very low performance (about 5MBps according to > iostat) in a guest under Qemu/KVM. > 3.2.7-1-ARCH x86_64 Arch LinuxYes, the performance goes down as some pathological should-not-happen code path is taken. I myself haven''t seen this error recently during testing, but at the time I did, it slowed down the machine for a while, ie. it''s not a inifinite loop. Seems there''s a dark corner of space reservations left for Josef. david -- 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
I''ve just seen this too on Fedora 16 while I was investigating an NFS issue. I was trying to copy a file from an NFS mount to a btrfs partition. The NFS transfers for large files were occurring in bursts for some reason and I was aborting the copy at times. This NFS problem was not related to btrfs (cat NFS file > /dev/null was also bursting and slow). Originally I ran 3.2.1-3.fc16, but just upgraded to 3.2.7-1.fc16. The file system was formatted with 3.2.1 originally. I can''t say for sure what caused this - whether it was the NFS being slow, the copy being interrupted, or btrfs itself. Regards, Nik On Mon, Feb 27, 2012 at 9:03 AM, David Sterba <dave@jikos.cz> wrote:> On Sat, Feb 25, 2012 at 09:14:01AM +1030, Jordan Windsor wrote: >> I''m running Ubuntu under KVM, with btrfs on the host where the >> Qemu/KVM image is stored, the VM was also running at the time. I was >> going to check something unrelated in the dmesg output, as I did that >> I noticed some errors in it about btrfs here they are: >> >> >> [ 4294.431807] btrfs: block rsv returned -28 >> [ 4294.431811] ------------[ cut here ]------------ >> [ 4294.431831] WARNING: at fs/btrfs/extent-tree.c:5985 > > This is a warning and it shows up from time to time, accross recent > releases. > >> This didn''t cause any crashes or related issues, also unrelated (I >> think?) is that I get very low performance (about 5MBps according to >> iostat) in a guest under Qemu/KVM. >> 3.2.7-1-ARCH x86_64 Arch Linux > > Yes, the performance goes down as some pathological should-not-happen > code path is taken. I myself haven''t seen this error recently during > testing, but at the time I did, it slowed down the machine for a while, > ie. it''s not a inifinite loop. Seems there''s a dark corner of > space reservations left for Josef. > > > david > -- > 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-- 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