[HBASE-20981] Rollback stateCount accounting thrown-off when exception out of rollbackState

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.1
• Fix Version/s: 3.0.0-alpha-1, 2.1.1, 2.0.2
• Component/s: amv2
• Hadoop Flags: Reviewed
• Assignee: Jack Bearden
• Reporter: Michael Stack
• Created: 30/Jul/18 17:49
• Updated: 25/Jan/20 22:42
• Resolved: 11/Aug/18 18:59

Description

Found by might allan163 over in HBASE-20893. Quoting Allan:

But, there is truly a bug here,

  @Override
  protected void rollback(final TEnvironment env)
      throws IOException, InterruptedException {
    if (isEofState()) stateCount--;
    try {
      updateTimestamp();
      rollbackState(env, getCurrentState());
      stateCount--;
    } finally {
      updateTimestamp();
    }
  }
We need to decrease the stateCount when rolling back, so we can rollback for the previous state correctly. But. since a exception is thrown, the decrease for stateCount never happen. So ProcedureExecutor will continue to rollback for only one state(the one throw a exception) until the end of the execution stack.

Issue Links

• is related to: HBASE-20893 Data loss if splitting region while ServerCrashProcedure executing

Sub-Tasks

• Port HBASE-20981 in 2.2 & 2.3: Resolved