Bug 204377
| Summary: | Deadlock with btrfs-transacti | ||
|---|---|---|---|
| Product: | File System | Reporter: | Drazen Kacar (drazen.kacar) |
| Component: | btrfs | Assignee: | BTRFS virtual assignee (fs_btrfs) |
| Status: | NEW --- | ||
| Severity: | normal | CC: | stf_xl |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 5.2.4 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
| Attachments: | dmesg | ||
Created attachment 284045 [details] dmesg Virtual machine in VmWare, 4 CPUs, 8 GB RAM. # cat /etc/redhat-release CentOS Linux release 7.6.1810 (Core) # uname -a Linux prod-dbsnap-01 5.2.4-1.el7.elrepo.x86_64 #1 SMP Sun Jul 28 08:10:57 EDT 2019 x86_64 x86_64 x86_64 GNU/Linux # btrfs --version btrfs-progs v5.2.1 # btrfs qgroup show /data/pg_data ERROR: can't list qgroups: quotas not enabled # grep btrfs /proc/mounts /dev/sdb /data/pg_data btrfs rw,noatime,compress-force=zstd:3,ssd,space_cache,subvolid=5,subvol=/ 0 0 # btrfs filesystem usage /data/pg_data Overall: Device size: 2.00TiB Device allocated: 872.02GiB Device unallocated: 1.15TiB Device missing: 0.00B Used: 843.15GiB Free (estimated): 1.17TiB (min: 1.17TiB) Data ratio: 1.00 Metadata ratio: 1.00 Global reserve: 512.00MiB (used: 0.00B) Data,RAID0: Size:860.00GiB, Used:834.69GiB /dev/sdb 215.00GiB /dev/sdc 215.00GiB /dev/sdd 215.00GiB /dev/sde 215.00GiB Metadata,RAID0: Size:12.00GiB, Used:8.46GiB /dev/sdb 3.00GiB /dev/sdc 3.00GiB /dev/sdd 3.00GiB /dev/sde 3.00GiB System,RAID0: Size:16.00MiB, Used:64.00KiB /dev/sdb 4.00MiB /dev/sdc 4.00MiB /dev/sdd 4.00MiB /dev/sde 4.00MiB Unallocated: /dev/sdb 294.00GiB /dev/sdc 294.00GiB /dev/sdd 294.00GiB /dev/sde 294.00GiB Got deadlock between btrfs-transacti and postgres processes. # mpstat -P ALL 2 Linux 5.2.4-1.el7.elrepo.x86_64 (prod-dbsnap-01) 07/30/2019 _x86_64_ (4 CPU) 02:55:16 PM CPU %usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle 02:55:18 PM all 0.25 0.00 0.25 25.06 0.00 0.00 0.00 0.00 0.00 74.43 02:55:18 PM 0 0.51 0.00 0.51 0.00 0.00 0.00 0.00 0.00 0.00 98.99 02:55:18 PM 1 0.00 0.00 0.51 0.00 0.00 0.00 0.00 0.00 0.00 99.49 02:55:18 PM 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 02:55:18 PM 3 0.00 0.00 0.00 100.00 0.00 0.00 0.00 0.00 0.00 0.00 02:55:18 PM CPU %usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle 02:55:20 PM all 0.00 0.00 0.25 24.75 0.00 0.00 0.00 0.00 0.00 75.00 02:55:20 PM 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 02:55:20 PM 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 02:55:20 PM 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 02:55:20 PM 3 0.51 0.00 0.51 98.99 0.00 0.00 0.00 0.00 0.00 0.00 ... Average: CPU %usr %nice %sys %iowait %irq %soft %steal %guest %gnice %idle Average: all 0.13 0.00 0.25 24.92 0.00 0.00 0.00 0.00 0.00 74.70 Average: 0 0.22 0.00 0.36 0.00 0.00 0.00 0.00 0.00 0.00 99.42 Average: 1 0.07 0.00 0.14 0.00 0.00 0.00 0.00 0.00 0.00 99.78 Average: 2 0.07 0.00 0.07 0.00 0.00 0.00 0.00 0.00 0.00 99.86 Average: 3 0.14 0.00 0.29 99.57 0.00 0.00 0.00 0.00 0.00 0.00 # ps -p 1411 -o pid,state,wchan:30,comm PID S WCHAN COMMAND 1411 D lock_extent_buffer_for_io btrfs-transacti There's nothing running on CPUs. I'm attaching dmesg with a bunch of info obtained from various /proc/sysrq-trigger commands.