We are comparing the performance on oracle database when the AIX is configured with SMT 4 and NO SMT, I create the following scripts to test the elapsed time when running multiple oracle queries at one time. 1. The PL/SQL code: the procedure smttestproc measures the elapsed time in milliseconds. create table SMTTEST (roundid int,totalprocess int, processid int,starttime timestamp,endtime timestamp,elapsedmilliseconds number(10,0),tablerows int); create or replace procedure smttestproc(roundid in int,totalprocess in int,processid in int) is begintime timestamp; endtime timestamp; elapsedmilliseconds number(10,0); tablerows int; begin select count(*) into tablerows from table_line; select systimestamp into begintime from dual; select count(*) into tablerows from table_line,table_line; select systimestamp into endtime from dual; select sum( (extract(hour from endtime)-extract(hour from endtime))*3600+ (extract(minute from endtime)-extract(minute from begintime