#include <db.h>

int
DB_ENV->set_lg_max(DB_ENV *dbenv, u_int32_t lg_max);

Description

Set the maximum size of a single file in the log, in bytes. Because DB_LSN file offsets are unsigned four-byte values, the set value may not be larger than the maximum unsigned four-byte value. By default, or if the value is set to 0, a size of 10MB is used. The size of the log file must be at least four times the size of the in-memory log buffer (see DB_ENV->set_lg_bsize).

See Log File Limits for more information.

The DB_ENV->set_lg_max interface may be used only to configure Berkeley DB before the DB_ENV->open interface is called.

The DB_ENV->set_lg_max function returns a non-zero error value on failure and 0 on success.

The database environment's log file 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_max", 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 DB_ENV->set_lg_max function may fail and return a non-zero error for the following conditions:

EINVAL

An invalid flag value or parameter was specified.

Called after DB_ENV->open was called.

The size of the log file is less than four times the size of the in-memory log buffer.

The specified log file size was too large.

The DB_ENV->set_lg_max function may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions. If a catastrophic error has occurred, the DB_ENV->set_lg_max function may fail and return DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail in the same way.

See Also