Oracle FAQ Your Portal to the Oracle Knowledge Grid

Home -> Community -> Mailing Lists -> Oracle-L -> Re: 9i doubts

Re: 9i doubts

From: Jared Still <>
Date: Sat, 03 May 2003 19:16:39 -0800
Message-ID: <>

why not build a 9i database, test each of these, and let us know the results?

Sorry, too many questions for me, some of which the answers are easily ascertained from the documentation.


On Friday 02 May 2003 22:56, wrote:
> Hello list
> I had some doubts I had after going thru Oracle documentation for 9i
> release2 :
> Q1. Which components of the sga other than the shared pool and the
> database buffer cache are dynamically sizable ?
> Q2. Which components of the sga allocate memory in granules and which do
> not ?
> Q3. If I specify sga_max_size=199M then does upon startup, oracle allocate
> this much memory straight away and then start allocating it to various sga
> components ?
> Q4. If the answer to the above question is yes then does oracle allocate
> 199M or an integral multiple of granule size ? ( 199M is not an exact
> integral multiple of 16 MB or 8MB)
> Q5. "SMON is responsible for coalescing contiguous free extents within
> dictionay managed tablespaces"
> => then who does the coalescing within locally managed tablespaces ?
> Q6. Can the oracle block size be smaller than the operating system block
> size ?
> Q7. Is data dictionary information cached in the database buffer cache
> also ?
> Q8. The administrators guide says "Whenever a transaction is commited a
> system change number is assigned to identify the redo records for each
> commited transaction."
> => is the scn assigned to the transaction ( which means that every
> statement in the transaction gets the same scn)
> or is a different scn assigned to each and every statement within the
> transaction " ?
> Q9. "When checkpoints are not set to occur between log switches , make all
> groups the same size to guarantee that checkpoints occur at regular
> intervals" {SAG pg 7-9}
> How do I disable checkpoints between log switches ?
> should i use fast_start_mttr_target ?
> Q10. Do I have to shutdown and then go to the mount state just to rename a
> log member ? Can't it be done when the dataabse is open and the group is
> not current or active ?
> Q11. Where are the free list groups and the freelists stored ?
> Q12 When the server process does not find a block in the database buffer
> cache it fetches it from the datafile and leaves a copy in the buffer cache
> . What happens when Oracle has to reconstruct a read-consistent image from
> the undo segment ? ( example when a row has changes that were not committed
> at the start of the query ) . Will the existing copy of the data block in
> the buffer cache be over-written ?

Please see the official ORACLE-L FAQ:
Author: Jared Still

Fat City Network Services    -- 858-538-5051
San Diego, California        -- Mailing list and web hosting services
To REMOVE yourself from this mailing list, send an E-Mail message
to: (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).
Received on Sat May 03 2003 - 22:16:39 CDT

Original text of this message