DB_ENV->set_lk_max_lockers()
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## DB_ENV->set_lk_max_lockers()

    #include <db.h>

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

Sets the maximum number of locking entities 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 lockers. For specific information on configuring the size of the lock subsystem, see Configuring locking: sizing the system.

The database environment's maximum number of lockers 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_lockers", one or more whitespace characters, and the number of lockers. 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_lockers()` method configures a database environment, not only operations performed using the specified DB_ENV handle.

The `DB_ENV->set_lk_max_lockers()` 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_lockers()` will be ignored.

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

### Parameters

#### max

The max parameter is the maximum number simultaneous locking entities supported by the Berkeley DB environment.

### Errors

The `DB_ENV->set_lk_max_lockers()` 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

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