Re: interpreting statspack reports ( PX Deq )

jmsalvo_at_ihug.com.au (john) wrote in message news:<fa6269d2.0206100047.200f790e_at_posting.google.com>...
> Event Waits Time (cs)
> Wt Time
> -------------------------------------------- ------------ ------------
> -------
> PX Deq Credit: send blkd 334,105 176,389
> 37.10
> PX Deq: Execution Msg 35,860 57,729
> 12.14
> PX Deq: Table Q Normal 865,976 50,065
> 10.53
> PX Deq: Execute Reply 22,596 46,401
> 9.76
> db file scattered read 285,813 44,901
> 9.44

A metalink document at
http://metalink.oracle.com/metalink/plsql/ml2_documents.showDocument?p_database_id=FOR&p_id=113386.999 has this explanation:

PX Deq:Table Q Normal
No description available
Parameters:

P1: sleeptime/senderid 
P2: passes 
P3: 

PX Deq:Execution Msg
Definition:PQ slave is waiting to be told what to do. This is one of the main events used in a parallel query dialogue as the slave is told to parse / execute / fetch etc.. Parameters: P1: sleeptime/senderid
P2: passes

PX Deq: Execute Reply
Definition: QC is waiting for a reply
Parameters: P1: sleeptime/senderid
P2: passes

PX Deq Credit: send blkd
Definition: Waiting for the CREDIT
Parameters: P1: sleeptime/senderid
P2: passes
P3: qref
This Wait Event replaces Parallel_Query_Dequeue, the name was changed in Oracle8i.

PX Deq Credit: need buffer
Definition: Waiting for the CREDIT so we can fill a buffer to send data.
Parameters: P1: sleeptime/senderid
P2: passes
P3: qref
This Wait Event replaces Parallel_Query_Dequeue, the name changed in Oracle8i.

If you search on Metalink carefully, you'll find a number of messages from Jonathan Lewis about these events. Oracle usually say these are idle waits and can be ignored. Whether that's true depends on how you look at it.

I don't know where to find a complete list of wait events and latches. I asked this question here before.

Yong Huang Received on Tue Jun 11 2002 - 00:11:16 CDT