public DbTxnStat txn_stat(int flags)
The DbEnv.txn_stat method returns the transaction subsystem statistics.
The flags value must be set to 0 or
the following value:
- Reset statistics after returning their values.
The DbEnv.txn_stat method creates a DbTxnStat object encapsulating the
transaction region statistics. The following data fields are available
from the DbTxnStat object:
- public DbLsn st_last_ckp;
- The LSN of the last checkpoint.
- public long st_time_ckp;
- The time the last completed checkpoint finished (as the number of seconds
since the Epoch, returned by the IEEE/ANSI Std 1003.1 (POSIX) time interface).
- public int st_last_txnid;
- The last transaction ID allocated.
- public int st_maxtxns;
- The maximum number of active transactions possible.
- public int st_nactive;
- The number of transactions that are currently active.
- public int st_maxnactive;
- The maximum number of active transactions at any one time.
- public int st_nbegins;
- The number of transactions that have begun.
- public int st_naborts;
- The number of transactions that have aborted.
- public int st_ncommits;
- The number of transactions that have committed.
- public int st_nrestores;
- The number of transactions that have been restored.
- public int st_regsize;
- The size of the region.
- public int st_region_wait;
- The number of times that a thread of control was forced to wait before
obtaining the region lock.
- public int st_region_nowait;
- The number of times that a thread of control was able to obtain
the region lock without waiting.
- public Active st_txnarray;
- The array of active transactions. Each element of the array is an object
of type DbTxnStat.Active, a top level inner class, that has the following
- public int txnid;
- The transaction ID of the transaction.
- public int parentid;
- The transaction ID of the parent transaction (or 0, if no parent).
- public DbLsn lsn;
- The current log sequence number when the transaction was begun.
The DbEnv.txn_stat method throws an exception that encapsulates a non-zero error value on
The DbEnv.txn_stat method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbEnv.txn_stat method may fail and
throw a DbRunRecoveryException,
in which case all subsequent Berkeley DB calls will fail in the same way.
Transaction Subsystem and Related Methods
Copyright Sleepycat Software