Re: Number of Transaction Slots

Taking a different tack - it doesn't really matter very much what the maximum is, as you don't want to have more than 5 concurrent transactions per rollback segment or you start losing space in rollback blocks in a big way. (There is a block reuse pool limited to 5 blocks). And you start getting contention on the segment header undo block if the concurrency goes too high.

Using a formula instead of just looking is perhaps a bit pointless - minor details can change over time, rapidly making the formula incorrect. As the economist said:

    "Yes, I know it works in practice, but does     it work in theory."

Jonathan Lewis
http://www.jlcomp.demon.co.uk

Next Seminar - UK, April 3rd - 5th
http://www.jlcomp.demon.co.uk/seminar.html

Host to The Co-Operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/faq/ind_faq.html

Author of:
Practical Oracle 8i: Building Efficient Databases

-----Original Message-----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Date: 07 March 2002 21:25

|
|Thanks Robert, and thanks once again, Gopal.
|
|Now, metalink also has a formula for finding the number of
transaction
|slots (DOC ID: 177926.999), and Steve Adams too explains precisely
how he
|arrived at that number of 21 slots for a 2K block size at
|http://www.ixora.com.au/q+a/0008/29204045.htm without dumping the
header
|block, from v$TYPE_SIZE.
|
|But then the metalink has one formula, if the rollback segment has a
fixed
|number of extents, and another if it has unlimited number of extents.
Steve
|Adams also does refer to the extent control headers, but I think he's
done
|either of the one assumptions.

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (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).



Content-Type: text/plain; name="ReadMe.txt"; charset="us-ascii"
Content-Transfer-Encoding: 7bit

The previous attachment was filtered out by the ListGuru mailing
software at fatcity.com because binary attachments are not appropriate
for mailing lists.  If you want a copy of the attachment which was
removed, contact the sender directly and ask for it to be sent to
you by private E-mail.

This warning is inserted into all messages containing binary
attachments which have been removed by ListGuru.  If you have questions
about this message, contact Postmaster_at_fatcity.com for clarification.

------_=_NextPart_001_01C1C75D.FA669F80--
-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (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).



application/ms-tnef attachment: winmail.dat