DB_ENV->set_lk_max_locks()

#include <db.h>

int
DB_ENV->set_lk_max_locks(DB_ENV *dbenv, u_int32_t max);  

Set the maximum number of locks supported by the Berkeley DB environment. This value is used by DB_ENV->open() to estimate how much space to allocate for various lock-table data structures. The default value is 1000 locks. For specific information on configuring the size of the lock subsystem, see Configuring locking: sizing the system.

The database environment's maximum number of locks 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_lk_max_locks", one or more whitespace characters, and the number of locks. Because the DB_CONFIG file is read when the database environment is opened, it will silently overrule configuration done before that time.

The DB_ENV->set_lk_max_locks() method configures a database environment, not only operations performed using the specified DB_ENV handle.

The DB_ENV->set_lk_max_locks() method may not be called after the DB_ENV->open() method is called. If the database environment already exists when DB_ENV->open() is called, the information specified to DB_ENV->set_lk_max_locks() will be ignored.

The DB_ENV->set_lk_max_locks() method returns a non-zero error value on failure and 0 on success.

Parameters

max

The max parameter is the maximum number of locks supported by the Berkeley DB environment.

Errors

The DB_ENV->set_lk_max_locks() method may fail and return one of the following non-zero errors:

EINVAL

If the method was called after DB_ENV->open() was called; or if an invalid flag value or parameter was specified.

Class

DB_ENV, DB_LOCK

See Also

Locking Subsystem and Related Methods