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I swear I thought I read that px deq waits were idle waits. Do you
still see these waits with parallel automatic tuning on? I'm not
suggesting that turning it all to automatic is the answer, but it seems
to work rather well on the box I'm testing. Maybe that's because I
don't know better.
My impression of cache buffers chains waits is processes fighting over a buffer. Am I wrong? With the larger buffer cache I've been testing, these waits have nearly gone away during data loads.
Comments?
-----Original Message-----
From: DEEDSD_at_Nationwide.com [mailto:DEEDSD_at_Nationwide.com]
Sent: Tuesday, June 15, 2004 8:27 AM
To: oracle-l_at_freelists.org
Subject: Re: [Fwd: Re: I may never see this again. SGA]
This system is a wonderful example of something having 'an infinite capacity to wait'.
My best solution is to club the consultants that suggested default
parallel
degrees between 8 and 16 be placed on the tables, then club the
developers
that allowed it. Following the clubbing, immediate sacking is
recommended.
Then, cut down the default parallelism to a reasonable level if people
still insist on using parallel query, then redesign the ~550 tables that
have 180+ partitions each into a good logical and physical design and
hire
developers that know what they are doing to fix the application.
After all that is done, the PX Deq waits and cache buffers chains waits will take care of themselves....
I think you know the database of which I speak, Joe...
<jtesta_at_dmc-it.com> T Sent by: To: <oracle-l_at_freelists.org> oracle-l-bounce_at_freelis cc: ts.org bcc: Subject: [Fwd: Re: I may never see this again. SGA] 06/14/2004 04:41 PM Please respond to oracle-l
Ok i'll bite, whats the solution for the PX Deq and Cache Buffer chains waits?
joe
original message below>
>
Bah.
On a 24-CPU sun box w/96 GB of memory, one 2 TB database. You should see the PX Deq and cache buffers chains waits!! Completely obscene. It's a train wreck. But, we have to do what the customers demand...
Connected to:
Oracle9i Enterprise Edition Release 9.2.0.4.0 - 64bit Production With
the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.4.0 - Production
SQL> show sga
Total System Global Area 7.2311E+10 bytes
Fixed Size 835056 bytes Variable Size 2499805184 bytes Database Buffers 6.9810E+10 bytes Redo Buffers 319488 bytesPlease see the official ORACLE-L FAQ: http://www.orafaq.com
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