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<title>Berkeley DB: DbEnv.lock_stat</title>
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<h1>DbEnv.lock_stat</h1>
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import com.sleepycat.db.*;
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public DbLockStat lock_stat(int flags)
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<p>The DbEnv.lock_stat method returns the locking subsystem statistics.
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<p>The <b>flags</b> value must be set to 0 or
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<p><dt><a name="Db.DB_STAT_CLEAR">Db.DB_STAT_CLEAR</a><dd>Reset statistics after returning their values.
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<p>The DbEnv.lock_stat method creates a DbLockStat object encapsulating the
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lock region statistics. The following data fields are available from
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the DbLockStat object:
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<dt>public int st_id;<dd>The last allocated locker ID.
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<dt>public int st_cur_maxid;<dd>The current maximum unused locker ID.
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<dt>public int st_nmodes;<dd>The number of lock modes.
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<dt>public int st_maxlocks;<dd>The maximum number of locks possible.
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<dt>public int st_maxlockers;<dd>The maximum number of lockers possible.
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<dt>public int st_maxobjects;<dd>The maximum number of lock objects possible.
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<dt>public int st_nlocks;<dd>The number of current locks.
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<dt>public int st_maxnlocks;<dd>The maximum number of locks at any one time.
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<dt>public int st_nlockers;<dd>The number of current lockers.
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<dt>public int st_maxnlockers;<dd>The maximum number of lockers at any one time.
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<dt>public int st_nobjects;<dd>The number of current lock objects.
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<dt>public int st_maxnobjects;<dd>The maximum number of lock objects at any one time.
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<dt>public int st_nrequests;<dd>The total number of locks requested.
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<dt>public int st_nreleases;<dd>The total number of locks released.
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<dt>public int st_nnowaits;<dd>The total number of lock requests failing because
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<a href="../api_java/lock_vec.html#DB_LOCK_NOWAIT">Db.DB_LOCK_NOWAIT</a> was set.
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<dt>public int st_nconflicts;<dd>The total number of locks not immediately available due to conflicts.
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<dt>public int st_ndeadlocks;<dd>The number of deadlocks.
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<dt>public int st_locktimeout;<dd>Lock timeout value.
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<dt>public int st_nlocktimeouts;<dd>The number of locks that have timed out.
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<dt>public int st_txntimeout;<dd>Transaction timeout value.
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<dt>public int st_ntxntimeouts;<dd>The number of transactions that have timed out. This value is also a
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component of <b>st_ndeadlocks</b>, the total number of deadlocks
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<dt>public int st_regsize;<dd>The size of the lock region.
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<dt>public int st_region_wait;<dd>The number of times that a thread of control was forced to wait before
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obtaining the region lock.
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<dt>public int st_region_nowait;<dd>The number of times that a thread of control was able to obtain
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the region lock without waiting.
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<p>The DbEnv.lock_stat method throws an exception that encapsulates a non-zero error value on
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<p>The DbEnv.lock_stat method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
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If a catastrophic error has occurred, the DbEnv.lock_stat method may fail and
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throw a <a href="../api_java/runrec_class.html">DbRunRecoveryException</a>,
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in which case all subsequent Berkeley DB calls will fail in the same way.
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<a href="../api_java/env_class.html">DbEnv</a>, <a href="../api_java/lock_class.html">DbLock</a>
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<a href="../api_java/lock_list.html">Locking Subsystem and Related Methods</a>
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