Berkeley DB: DbEnv.log_stat
Description: Berkeley DB: An embedded database programmatic toolkit.
Keywords: embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++

# DbEnv.log_stat |

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    import com.sleepycat.db.*;

    public DbLogStat log_stat()
    	throws DbException;

# Description

The DbEnv.log_stat method creates a DbLogStat object encapsulating a statistical structure. The log region statistics are stored in a DbLogStat object. The following data fields are available from the DbLogStat object:

Statistical structures are created in allocated memory. If db_malloc is non-NULL, it is called to allocate the memory, otherwise, the library function malloc(3) is used. The function db_malloc must match the calling conventions of the malloc(3) library routine. Regardless, the caller is responsible for deallocating the returned memory. To deallocate returned memory, free the returned memory reference, references inside the returned memory do not need to be individually freed.

The log region statistics are stored in a structure of type DB_LOG_STAT. The following DB_LOG_STAT fields will be filled in:

public int st_magic;
  The magic number that identifies a file as a log file.
public int st_version;
  The version of the log file type.
public int st_regsize;
  The size of the region.
public int st_mode;
  The mode of any created log files.
public int st_lg_bsize;
  The in-memory log record cache size.
public int st_lg_max;
  The maximum size of any individual file comprising the log.
public int st_w_mbytes;
  The number of megabytes written to this log.
public int st_w_bytes;
  The number of bytes over and above st_w_mbytes written to this log.
public int st_wc_mbytes;
  The number of megabytes written to this log since the last checkpoint.
public int st_wc_bytes;
  The number of bytes over and above st_wc_mbytes written to this log since the last checkpoint.
public int st_wcount;
  The number of times the log has been written to disk.
public int st_wcount_fill;
  The number of times the log has been written to disk because the in-memory log record cache filled up.
public int st_scount;
  The number of times the log has been flushed to disk.
public int st_cur_file;
  The current log file number.
public int st_cur_offset;
  The byte offset in the current log file.
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 DbEnv.log_stat method throws an exception that encapsulates a non-zero error value on failure.

# Errors

The DbEnv.log_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.log_stat method may fail and throw a DbRunRecoveryException, in which case all subsequent Berkeley DB calls will fail in the same way.

### Class

DbEnv

# See Also

DbEnv.set_lg_bsize, DbEnv.set_lg_max, DbEnv.log_archive, DbEnv.log_compare, DbEnv.log_file, DbEnv.log_flush, DbEnv.log_get, DbEnv.log_put, DbEnv.log_register, DbEnv.log_stat and DbEnv.log_unregister.`

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