Berkeley DB: DbLockTab.stat
Полезная информация

DbLockTab.stat


import com.sleepycat.db.*;

public DbLockStat stat() throws DbException;

Description

The DbLockTab.stat method creates a DbLockStat object encapsulating a statistical structure.

The lock region statistics are stored in a DbLockStat object. The following data fields are available from the DbLockStat object:

public int st_magic;
The magic number that identifies a file as a lock file.
public int st_version;
The version of the lock file type.
public int st_refcnt;
The number of references to the region.
public int st_regsize;
The size of the region.
public int st_maxlocks;
The maximum number of locks possible.
public int st_nmodes;
The number of lock modes.
public int st_numobjs;
The number of unique objects locked.
public int st_nlockers;
The number of unique lockers.
public int st_nconflicts;
The total number of locks not immediately available due to conflicts.
public int st_nrequests;
The total number of locks requested.
public int st_nreleases;
The total number of locks released.
public int st_ndeadlocks;
The number of deadlocks detected.
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.

The DbLockTab.stat method throws an exception that encapsulates an errno on failure.

Errors

If a fatal error occurs in Berkeley DB, the DbLockTab.stat method may fail and throw a DbRunRecoveryException, at which point all subsequent database calls will also fail in the same way.

The DbLockTab.stat method may fail and throw an exception for any of the errors specified for the following Berkeley DB and C library functions: abort(3), fcntl(3), fprintf(3), getpid(3), malloc(3), and memset(3).

Class

DbLockTab

See Also

DbLockTab.close, DbLockTab.detect, DbLockTab.get, DbLockTab.id, DbLockTab.open, DbLockTab.stat DbLockTab.unlink and DbLockTab.vec.