Viewing file:  env_set_tas_spins.html (3.79 KB) -rw-r--r--
Select action/file-type:
 (+) | (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
Berkeley DB: DB_ENV->set_tas_spins
DB_ENV->set_tas_spins
|
 |
#include <db.h>
int
DB_ENV->set_tas_spins(DB_ENV *dbenv, u_int32_t tas_spins);
int
DB_ENV->get_tas_spins(DB_ENV *dbenv, u_int32_t *tas_spinsp);
Description: DB_ENV->set_tas_spins
Specify that test-and-set mutexes should spin tas_spins times
without blocking. The value defaults to 1 on uniprocessor systems and
to 50 times the number of processors on multiprocessor systems.
The database environment's test-and-set spin count 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_tas_spins", one or more whitespace characters,
and the number of spins.
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_tas_spins method configures operations performed using the specified
DB_ENV handle, not all operations performed on the underlying
database environment.
The DB_ENV->set_tas_spins method may be called at any time during the life of the
application.
The DB_ENV->set_tas_spins method
returns a non-zero error value on failure
and 0 on success.
Parameters
- tas_spins
- The tas_spins parameter is the number of spins test-and-set
mutexes should execute before blocking.
Errors
The DB_ENV->set_tas_spins method
may fail and return one of the following non-zero errors:
- EINVAL
- An
invalid flag value or parameter was specified.
Description: DB_ENV->get_tas_spins
The DB_ENV->get_tas_spins method returns the test-and-set spin count.
The DB_ENV->get_tas_spins method may be called at any time during the life of the
application.
The DB_ENV->get_tas_spins method
returns a non-zero error value on failure
and 0 on success.
Parameters
- tas_spinsp
- The DB_ENV->get_tas_spins method returns the
test-and-set spin count in tas_spinsp.
Class
DB_ENV
See Also
Database Environments and Related Methods
Copyright (c) 1996-2004 Sleepycat Software, Inc. - All rights reserved.
|