Quick positioning when the oracle system is busy

When the oracle system is busy, quickly locate 1. Check the current number of connections select count (*) from gv $ session; www.2cto.com 2. Here we are the bs architecture, let's take a look at the general situation of the session for the application. 2.1 sqlselect gs executed. inst_id, gs. SID, gvs. SQL _text, gs. SERIAL #, gs. STATUS, gs. EVENT, gs. WAIT_CLASS, gs. WAIT_TIME, gs. SECONDS_IN_WAIT, p. spid, gs. logon_time from gv $ process p, gv $ session gs left join gv $ SQL gvs on gs. SQL _id = gvs. SQL _id where gs. PROGRAM = 'jdbc Thin client' and gs. paddr = p. ADDR; Note: 1) the State field has four meanings: (1) Waiting: the SESSION is Waiting for this event. (2) Waited unknown time: the time cannot be obtained because the value of timed_statistics is set to false. It indicates a wait, but the time is short. (3) Wait short time: indicates that a Wait has occurred. However, because the Wait time is very short and does not exceed one time unit, no records are recorded. (4) Waited knnow time: if the session waits and receives the required resources, it enters the State from waiting. Www.2cto.com 2). The Wait_time value also has four meanings: (1) value> 0: Last wait time (unit: 10 ms), not waiting currently. (2) value = 0: the session is waiting for the current event. (3) value =-1: The last wait time is less than one statistical unit, and the current status is not waiting. (4) value =-2: The time statistics status is not set to available, and is not waiting. 3). Wait_time and Second_in_wait field values are related to state: (1) if the state value is Waiting, the wait_time value is useless. The Second_in_wait value is the actual wait time (unit: seconds ). (2) If the state value is Wait unknow time, the wait_time value and Second_in_wait value are useless. (3) If the state value is Wait short time, the wait_time value and Second_in_wait value are useless. (4) If the value of state is Waiting known time, the value of wait_time is the actual Waiting time (unit: seconds), and the value of Second_in_wait is useless.