DbEnv::set_lg_max

API Ref

#include <db_cxx.h>

int DbEnv::set_lg_max(u_int32_t lg_max);

int DbEnv::get_lg_max(u_int32_t *);


Description: DbEnv::set_lg_max

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

See Log File Limits for more information.

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.

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

The DbEnv::set_lg_max method may be called at any time during the life of the application.

If no size is specified by the application, the size last specified for the database region will be used, or if no database region previously existed, the default will be used.

The DbEnv::set_lg_max 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_max
The lg_max parameter is the size of a single log file, in bytes.

Errors

The DbEnv::set_lg_max method may fail and throw DbException, 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; 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; or if an invalid flag value or parameter was specified.

Description: DbEnv::get_lg_max

The DbEnv::get_lg_max method returns the maximum log file size.

The DbEnv::get_lg_max method may be called at any time during the life of the application.

The DbEnv::get_lg_max 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_maxp
The DbEnv::get_lg_max method returns the maximum log file size in lg_maxp.

Class

DbEnv, DbLogc, DbLsn

See Also

Logging Subsystem and Related Methods

APIRef

Copyright (c) 1996-2003 Sleepycat Software, Inc. - All rights reserved.