DbEnv::set_lg_regionmax

APIRef

#include <db_cxx.h>

int DbEnv::set_lg_regionmax(u_int32_t lg_regionmax);

Description

Set the size of the underlying logging subsystem region, in bytes. By default, or if the value is set to 0, the base region size is 60KB. The log region is used to store filenames, and so may need to be increased in size if a large number of files will be opened and registered with the specified Berkeley DB environment's log manager.

The DbEnv::set_lg_regionmax method configures a database environment, not only operations performed using the specified DbEnv handle.

The DbEnv::set_lg_regionmax interface may not be called after the DbEnv::open interface is called. If the database environment already exists when DbEnv::open is called, the information specified to DbEnv::set_lg_regionmax will be ignored.

The DbEnv::set_lg_regionmax method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

The database environment's log region size may also be set using the environment's DB_CONFIG file. The syntax of the entry in that file is a single line with the string "set_lg_regionmax", one or more whitespace characters, and the size in bytes. Because the DB_CONFIG file is read when the database environment is opened, it will silently overrule configuration done before that time.

Errors

The DbEnv::set_lg_regionmax method may fail and throw an exception or return a non-zero error for the following conditions:

EINVAL
An invalid flag value or parameter was specified.

Called after DbEnv::open was called.

The DbEnv::set_lg_regionmax method may fail and throw an exception or return a non-zero error for errors specified for other Berkeley DB and C library or system methods. If a catastrophic error has occurred, the DbEnv::set_lg_regionmax method may fail and either return DB_RUNRECOVERY or throw a DbRunRecoveryException, in which case all subsequent Berkeley DB calls will fail in the same way.

Class

DbEnv, DbLogc, DbLsn

See Also

Logging Subsystem and Related Methods

APIRef

Copyright Sleepycat Software