PX Deq: Signal ACK

Normal 0 7.8 磅 0 2 false false false MicrosoftInternetExplorer4 A surprising wait event named “PX Deq: Signal ACK” --2010.12.15

When I query the v$session_wait,I see this wait events.

First,I will tell you that this is the idle wait. You may not be worried.

Then,how this wait event happen?

I saw the sql statement through the sid in v$sessoin_wait,v$session,v_sql

The sql statement is that:

select * from GV$GES_ENQUEUE

and this sid is active alaways.and the program is “PLSQL Developer”.

When I check the machine,It is what I use usually but there is no avtive in the “PLSQL Developer”. It’s so amazing!

Metalink:ID 257594.1

Versions:8.1 - 9.2 Documentation:None
Waiting Process:QC
The QC sends control messages to the slaves. The slaves have to send back acknowledge receipt. The QC waits to get this acknowledge receipt and this is the wait time for this event.

This is the same as the "Wait for slaves to ACK - Query Coord" wait event in Oracle 8.0.

来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/14730395/viewspace-681909/，如需转载，请注明出处，否则将追究法律责任。

转载于:http://blog.itpub.net/14730395/viewspace-681909/

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