DbEnv::set_lg_regionmax()

#include <db_cxx.h>

int
DbEnv::set_lg_regionmax(u_int32_t lg_regionmax); 

Set the size of the underlying logging area of the Berkeley DB environment, in bytes. By default, or if the value is set to 0, the minimum region size is used, approximately 128KB. 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 database environment's log region size may also be configured 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.

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

The DbEnv::set_lg_regionmax() method may not be called after the DbEnv::open() method 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.

Parameters

lg_regionmax

The lg_regionmax parameter is the size of the logging area in the Berkeley DB environment, in bytes.

Errors

The DbEnv::set_lg_regionmax() method may fail and throw a DbException exception, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:

EINVAL

If the method was called after DbEnv::open() was called; or if an invalid flag value or parameter was specified.

Class

DbEnv, DbLogc, DbLsn

See Also

Logging Subsystem and Related Methods