Critical Description
I was stress testing with the following setup:
- 8 servers (n1-standard-4 GCE boxes)
- created a bunch of 100-tablet tablets using loadgen until I had ~2500 replicas on each server
- mounted another server using sshfs and put cmeta on that mount point (to make slower cmeta writes)
- stress -c4 on all machines
- shut down a server and wait for re-replication (green ksck), restart the server, rinse repeat
Eventually I got a stuck tablet. ksck reports:
Tablet 271df8901d98442cb478593babd8a609 of table 'loadgen_auto_8e32cb07eb83458da4ec4d228bcb0f5a' is under-replicated: 1 replica(s) not RUNNING 20d4d86f182043398594b67492d13fdc (kudu513-8.gce.cloudera.com:7050): RUNNING [LEADER] c2ea8f22f4034bcc97e26c9236811960 (kudu513-1.gce.cloudera.com:7050): bad state State: STOPPED Data state: TABLET_DATA_COPYING Last status: Deleted tablet blocks from disk cd0997b908ad41839f56a1b61210f2d4 (kudu513-3.gce.cloudera.com:7050): RUNNING 1 replicas' active configs differ from the master's. All the peers reported by the master and tablet servers are: A = 20d4d86f182043398594b67492d13fdc D = 471027436ee8405ab7cdf8d22407696b B = c2ea8f22f4034bcc97e26c9236811960 C = cd0997b908ad41839f56a1b61210f2d4 The consensus matrix is: Config source | Voters | Current term | Config index | Committed? ---------------+------------------+--------------+--------------+------------ master | A* B C | | | Yes A | A* B C | 11 | 29 | Yes B | D B C | 9 | 23 | Yes C | A* B C | 11 | 29 | Yes
The leader ("A" above) just keeps reporting that it's failing to send requests to "B" because it's getting TABLET_NOT_RUNNING. So it never evicts it (the leader treats TABLET_NOT_RUNNING as a temporary condition assuming that it actually means BOOTSTRAPPING).
"B"'s last bit in the logs were:
I0920 16:41:48.556422 3808 tablet_copy_client.cc:209] T 271df8901d98442cb478593babd8a609 P c2ea8f22f4034bcc97e26c9236811960: tablet copy: Beginning tablet copy session from remote peer at address kudu513-8.gce.cloudera.com:7050
I0920 16:41:48.562335 3808 ts_tablet_manager.cc:1118] T 271df8901d98442cb478593babd8a609 P c2ea8f22f4034bcc97e26c9236811960: Deleting tablet data with delete state TABLET_DATA_COPYING
W0920 16:41:48.578610 3808 env_util.cc:277] Failed to determine if path is a directory: /data0/ts-data/tablet-meta/271df8901d98442cb478593babd8a609.kudutmp.2Tu0Uy: Not found: /data0/ts-data/tablet-meta/271df8901d98442cb478593babd8a609.kudutmp.2Tu0Uy: No such file or directory (error 2)
