Library Version 12.1.6.0

DbEnv::set_lk_max_locks()
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## DbEnv::set_lk_max_locks()

    #include <db_cxx.h>

    int
    DbEnv::set_lk_max_locks(u_int32_t max);

This method is deprecated. Instead, use DbEnv::set_memory_init(), DbEnv::set_memory_max(), and DbEnv::set_lk_tablesize().

Set the maximum number of locks supported by the Berkeley DB environment. This value is used by DbEnv::open() to estimate how much space to allocate for various lock-table data structures. The default value is 1000 locks. The final value specified for the locks should be more than or equal to the number of lock table partitions. 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 `DbEnv::set_lk_max_locks()` method configures a database environment, not only operations performed using the specified DbEnv handle.

The `DbEnv::set_lk_max_locks()` 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_lk_max_locks()` will be ignored.

The `DbEnv::set_lk_max_locks()` 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

#### max

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

### Errors

The `DbEnv::set_lk_max_locks()` 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, DbLock

### See Also

Locking Subsystem and Related Methods

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