gistfile1.txt

/******************************************************************//**
Save some CPU by testing the value of srv_thread_concurrency in inline
functions. */
static inline
void
innobase_srv_conc_enter_innodb(
/*===========================*/
        trx_t*  trx)    /*!< in: transaction handle */
{
        if (srv_thread_concurrency) {
                if (trx->n_tickets_to_enter_innodb > 0) {

                        /* If trx has 'free tickets' to enter the engine left,
                        then use one such ticket */

                        --trx->n_tickets_to_enter_innodb;

                } else if (trx->mysql_thd != NULL
                           && thd_is_replication_slave_thread(trx->mysql_thd)) {

                        UT_WAIT_FOR(
                                srv_conc_get_active_threads()
                                < srv_thread_concurrency,
                                srv_replication_delay * 1000);

                }  else {
                        srv_conc_enter_innodb(trx);
                }
        }
}