After a couple of weeks running Emby Server beta 4.2.0.24 on my OS6 Upgraded ReadyNAS Ultra 6 Plus I have faced a couple of ocassions where the NAS becomes unresposive.
Upon review of the logs prior to the "crash" - as I had to hard boot the NAS after it became unresponsive, I am seeing several entries such as these in the kernel.log of the NAS:
Jul 04 18:16:18 ReadyNAS6Ultra kernel: ------------[ cut here ]------------ Jul 04 18:16:18 ReadyNAS6Ultra kernel: WARNING: CPU: 0 PID: 22335 at fs/btrfs/extent-tree.c:7282 btrfs_free_extent+0x49/0xe9() Jul 04 18:16:18 ReadyNAS6Ultra kernel: Modules linked in: nv6lcd(O) vpd(PO) Jul 04 18:16:18 ReadyNAS6Ultra kernel: CPU: 0 PID: 22335 Comm: EmbyServer Tainted: P W O 4.4.178.x86_64.1 #1 Jul 04 18:16:18 ReadyNAS6Ultra kernel: Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS 080014 07/26/2010 Jul 04 18:16:18 ReadyNAS6Ultra kernel: 0000000000000000 ffff88009a0ff938 ffffffff883623e6 0000000000000000 Jul 04 18:16:18 ReadyNAS6Ultra kernel: 0000000000000009 ffff88009a0ff970 ffffffff880dbe55 ffffffff8828301e Jul 04 18:16:18 ReadyNAS6Ultra kernel: 0000000000013907 0000000000001000 ffff88005b09fb58 ffff8800a7af4000 Jul 04 18:16:18 ReadyNAS6Ultra kernel: Call Trace: Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff883623e6>] dump_stack+0x4d/0x63 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff880dbe55>] warn_slowpath_common+0x8f/0xa8 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff8828301e>] ? btrfs_free_extent+0x49/0xe9 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff88062feb>] warn_slowpath_null+0x15/0x17 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff8828301e>] btrfs_free_extent+0x49/0xe9 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff882acc09>] __btrfs_drop_extents+0xb2e/0xc85 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff882d4122>] btrfs_log_changed_extents+0x2ad/0x4fb Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff882d4e0c>] btrfs_log_inode+0xa9c/0xc2e Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff8807e2be>] ? default_wake_function+0xd/0xf Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff8808de2f>] ? autoremove_wake_function+0xd/0x2f Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff882d5b68>] btrfs_log_inode_parent+0x27b/0x733 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff880de31a>] ? __filemap_fdatawrite_range+0xbe/0xca Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff88298b8d>] ? wait_current_trans.isra.9+0x1d/0xdf Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff88297815>] ? join_transaction.isra.3+0x20/0x3ac Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff882d6e58>] btrfs_log_dentry_safe+0x55/0x70 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff882ae961>] btrfs_sync_file+0x226/0x2da Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff881416d2>] vfs_fsync_range+0x86/0x95 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff8811d08c>] ? vfs_write+0x152/0x160 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff881416f8>] vfs_fsync+0x17/0x19 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff88141726>] do_fsync+0x2c/0x45 Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff8814192d>] SyS_fsync+0xb/0xf Jul 04 18:16:18 ReadyNAS6Ultra kernel: [<ffffffff888e43ca>] entry_SYSCALL_64_fastpath+0x1e/0x8e Jul 04 18:16:18 ReadyNAS6Ultra kernel: ---[ end trace fc8abb8082935d98 ]---
For now, I am waiting the NAS to Resync (a couple of days) after the hard-boot I had to perform and will wait a few days with Emby disabled to validate if this is truly related to this situation. Messages like the above occur continuously for about 3 hours until I finally noticed the NAS was not responsive and I ended up hard-booting it.