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OK, a little more investigation shows:
So we'll see what Oracle Support says. Abraham, you might want to note this in your 9i->10g upgrade! :)
Rich
From: Jesse, Rich
Sent: Tuesday, November 28, 2006 3:47 PM
Cc: oracle-l_at_freelists.org
Subject: RE: Strange buffer resizing in 10gR2
Bingo! It shows that streams_pool_size was increased from 0 to the amount that db_buffer_size was decreased. Funny, but the entry for the increase comes logically in the view before the decrease, but I won't pick nits. :)
I don't think this would have been done manually, but I should be able to find something related to this behavior. Not used to this fun self-managing stuff just yet...
In the meantime, I have other fires to put out now...
Thanks, Charles!
Rich
From: Charles Schultz
Sent: Tuesday, November 28, 2006 3:07 PM
To: Jesse, Rich
Subject: Re: Strange buffer resizing in 10gR2
What does v$SGA_RESIZE_OPS show? If your SGA is resizing itself (due to sga_target = 0), the pools will show multiple dynamic entries. If the sizes are static, then they were set once the database started and have not resized dynamically. Does your spfile parameter show a value, or is it blank?
On 11/28/06, Jesse, Rich <Rich.Jesse_at_qg.com> wrote:
So, here I am sitting in a developer's class for our new ERP package,
and I decided to monitor the 10.2.0.2.0 DB on AIX 5.3 that all the dev's
individual JBoss servers are hammering. The first thing I noticed is
that the buffer cache appears to be a whopping 16MB. Hmmm...I could
have sworn that I set that higher. And I did.
The init.ora shows db_cache_size to be "50MB" and log_buffer to be
"524288". sga_target is unset and is "0" according to V$PARAMETER. The
init.ora file is dated November 5th, and V$INSTANCE shows that it's been
up and running since the 9th. There is no spfile (on purpose). Attempts to increase db_cache_size fail, like one would expect with the default sga_max_size. Confucious. There's some things in this database that are out of my control (despite my protests), but I don't see how this scenario could happen from within the DB. The only thing I can think of is that the instance was started with an SPFILE and that file has since been deleted, but I'm not sure how to prove this. Thoughts? Rich
-- http://www.freelists.org/webpage/oracle-lReceived on Wed Nov 29 2006 - 13:03:42 CST