Derby
  1. Derby
  2. DERBY-360

Add doc info to print lock table for timeout errors

    Details

    • Type: Improvement Improvement
    • Status: Open
    • Priority: Minor Minor
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: Documentation
    • Labels:
      None

      Description

      In version 10.1 docs,
      1. Admin guide - http://incubator.apache.org/derby/docs/adminguide/cadminlockvti83889.html, also a small section on timeouts should be added.

      To debug lock timeout errors, set derby.locks.monitor=true and derby.locks.deadlockTrace=true this will print the lock table information to the derby.log when the timeout happens. If you also set the derby.language.logStatementText=true , then all the statement executed on the system will be written out to the derby.log. Statement information also includes the transaction id on which the statement is being executed. Using the transaction id that is holding the lock in the lock table dump if you do a reverse search for the transaction id in derby.log, it is possible to narrow down which statements may be holding the locks.

      --------------
      Here is an example of lock table dump in derby.log on a lock timeout:
      ERROR 40XL2: A lock could not be obtained within the time requested. The lockTable dump is:
      2005-06-14 18:39:15.788 GMT
      XID |TYPE |MODE|LOCKCOUNT|LOCKNAME
      --------------------------------------------------------------------------------------

          • The following row is the victim ***
            146 |ROW |S |0 |(1,14)
          • The above row is the victim ***
            139 |TABLE |IX |1 |Tablelock
            146 |TABLE |IS |1 |Tablelock
            139 |ROW |X |1 |(1,14)
            --------------------------------------------------------------------------------------

        Activity

        Hide
        Knut Anders Hatlen added a comment -

        Changing issue type from bug to improvement.

        Show
        Knut Anders Hatlen added a comment - Changing issue type from bug to improvement.

          People

          • Assignee:
            Unassigned
            Reporter:
            Sunitha Kambhampati
          • Votes:
            0 Vote for this issue
            Watchers:
            0 Start watching this issue

            Dates

            • Created:
              Updated:

              Development