#include <db_cxx.h> int DbEnv::mutex_set_tas_spins(u_int32_t 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, up to a maximum of 200.
The database environment's test-and-set spin count 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_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 DbEnv::mutex_set_tas_spins()
method configures operations
performed using the specified
DbEnv handle, not all
operations performed on the underlying database environment.
The DbEnv::mutex_set_tas_spins()
method may be called at any time
during the life of the application.
The DbEnv::mutex_set_tas_spins()
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.
The DbEnv::mutex_set_tas_spins()
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: