RE: TC Enqueue waits
- From: "Khedr, Waleed" <Waleed.Khedr@xxxxxxx>
- To: <oracle-l@xxxxxxxxxxxxx>
- Date: Fri, 30 Apr 2004 13:50:14 -0400
PQ slaves uses direct reads bypassing the SGA to read the segment blocks =
which requires waiting to flush all committed
changes in the SGA (dirty buffers) of that object to make sure the PQ =
slaves
will access the most recent version of that object.
Regards,
Waleed
-----Original Message-----
From: Diego Cutrone [mailto:diegocutrone@xxxxxxxxxxxx]
Sent: Friday, April 30, 2004 4:25 PM
To: Oracle List
Subject: TC Enqueue waits
Hi List.
I have detected high enqueue waits in one instance.
After quering x$ksqst I realized most of them were TX and TC enqueues.
I'm on the TX enqueues by tracing some sessions. But I have never heard =
of TC enqueues
I have read that TC enqueue stands for "Thread Checkpoint enqueue".=20
Anybody knows what are they used for? what kind of resources they =
protect?
And I have another quick question:
I'm also seeing Parallel query events like:
PX Deq: Execution Msg
PX Idle Wait
PX qref latch=20
PX Deq: Execute Reply=20
PX Deq: Table Q Normal=20
PX Deq: Parse Reply=20
Does anybody know where I can get a description for them?=20
I'd like to know which ones can be ignored and which ones can't.
Thank you very much
Regards
Diego
----------------------------------------------------------------
Please see the official ORACLE-L FAQ: http://www.orafaq.com
----------------------------------------------------------------
To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
put 'unsubscribe' in the subject line.
--
Archives are at //www.freelists.org/archives/oracle-l/
FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
-----------------------------------------------------------------
----------------------------------------------------------------
Please see the official ORACLE-L FAQ: http://www.orafaq.com
----------------------------------------------------------------
To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
put 'unsubscribe' in the subject line.
--
Archives are at //www.freelists.org/archives/oracle-l/
FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
-----------------------------------------------------------------
Other related posts:
