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RE: Top level heaps/subheaps

From: Nelson, Allan <>
Date: Tue, 06 Jan 2004 06:44:26 -0800
Message-ID: <>


However, give serious thought to reading Jonathon Lewis' book Practical Oracle 8i prior to the Adams book unless you understand virtually everything in Jonathon's book.  Steve's book is excellent but verbosity is not one of his problems.
-----Original Message-----
From: [] On Behalf Of Bobak, Mark
Sent: Tuesday, January 06, 2004 8:10 AM
To: Multiple recipients of list ORACLE-L
Subject: RE: Top level heaps/subheaps

To quote Steve's book, aka "The Bible":
Freeable chunks contain objects that are normally needed for the duration of a session or call, and are freed thereafter.  However, they can sometimes be freed earlier, either in whole or in part.  Freeable chunks are not available for temporary removal from memory, because they are not recreatable.
If you don't have this book, go now, to the bookstore and buy it.  Then read it about 100 times, after which, if you're *really* bright, maybe 20% of it will have sunk in, at which point you'll know more than you'll ever need about Oracle internals.  ;-)  (Personally, I'm probably pushing 15% or so....;-))
PS  If you're not familiar with the book I refer to, it's "Oracle Internal Services for waits, latches, locks, and memory" by Steve Adams, published by O'Reilly.  Seriously, if you really want to know this stuff, get that book.

Mark J. Bobak
Oracle DBA
ProQuest Company
Ann Arbor, MI
"Imagination was given to man to compensate him for what he is not, and a sense of humor was provided to console him for what he is."  --Unknown

-----Original Message-----
From: Sultan Syed []
Sent: Tuesday, January 06, 2004 8:49 AM
To: Multiple recipients of list ORACLE-L
Subject: Top level heaps/subheaps

I am getting little confussion how the memory is allocated for
top-level heaps and subheaps in shared pool.
How can we know what are all the top-level heaps and subheaps and their hierarchy.
Is it possible to get it from any X$ tables.
Freeable chunks can be flushed out?If yes ,then why there should be another type as recreatable chunks?
Please explain.
Thanks in advance

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Author: Nelson, Allan

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Received on Tue Jan 06 2004 - 08:44:26 CST

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