DbEnv.txn_stat
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import com.sleepycat.db.*;
public DbTxnStat txn_stat(int flags)
throws DbException;
Description
The DbEnv.txn_stat method
creates a DbTxnStat object encapsulating a statistical structure.
The transaction region statistics are stored in a DbTxnStat object.
The following data fields are available from the DbTxnStat object:
The flags value must be set to 0 or
the following value:
- Db.DB_STAT_CLEAR
- Reset statistics after returning their values.
The transaction region statistics are stored in a structure of type
DB_TXN_STAT. The following DB_TXN_STAT fields will be filled in:
- public DbLsn st_last_ckp;
- The LSN of the last checkpoint.
- public DbLsn st_pending_ckp;
- The LSN of any checkpoint that is currently in progress. If
st_pending_ckp is the same as st_last_ckp there
is no checkpoint in progress.
- 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
fields:
- public int txnid;
- The Transaction ID.
- public DbLsn lsn;
- The Lsn of the begin record.
The DbEnv.txn_stat method throws an exception that encapsulates a non-zero error value on
failure.
Errors
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.
Class
DbEnv, DbTxn
See Also
DbEnv.set_tx_max,
DbEnv.set_tx_timestamp,
DbTxn.abort,
DbEnv.txn_begin,
DbEnv.txn_checkpoint,
DbTxn.commit,
DbTxn.discard,
DbTxn.id,
DbTxn.prepare,
DbEnv.txn_recover,
DbTxn.set_timeout
and
DbEnv.txn_stat.
Copyright Sleepycat Software