Is my db using MTS or shared server?

hi guys,
(Oracle 9i)
I read that to specify a database as MTS, you have to set the DISPATCHERS parameter. I do not have this set, yet, I can see values for mts_dispatchers? Why is this?
SQL> show parameters DISPAT
NAME TYPE VALUE
dispatchers string
max_dispatchers integer 5
mts_dispatchers string
mts_max_dispatchers integer 5
Can I be sure that my DB is in dedicated server mode, as dispatchers is not set?
thanks

Hi OracleGuy777,
In general, OLTP-type applications can be suitable for MTS, while batch, data warehouse, and decision support applications are usually not appropriate for MTS.
Conclusion: If a system is CPU-bound and that system has enough RAM to fit all of its processes into physical memory, then MTS should probably not be used on that system. (Please see links and notes bellow)
You can see the number of MTS sessions using:
SELECT COUNT (*)
FROM v$session
WHERE server != 'DEDICATED';To see the number of Dedicated ones, just change != for = in the WHERE clause.
Tom Kyte notes that the MTS should not be used without a "real reason" and he notes that shared server connections are slower than with dedicated database connections (Oracle's default behavior):
- http://asktom.oracle.com/pls/ask/f?p=4950:...D:5269794407347
+"Unless you have a real reason to use MTS -- don't."+
+"a shared server connection is by design "slower" than a dedicated server (more stuff goes on, more complex) it is most likely only getting in the way."+
+"In the golden age of client server way back when -- you might have 100 users connected to the database from 9-5, but at any point in time, only 5 or 6 of them were actually ACTIVE. In this case, 5 or 6 shared servers would be perfect."+
+"if you were cpu starved and context switching like mad -- the dedicated server connection could be running at a slow speed itself, slower than the extra work that shared server would impose. therefore, lightening up the load on the server could be beneficial...."+
Also take a look here: http://www.dba-oracle.com/t_mts_multithreaded_servers_shared.htm
If you decide to try it, here are the steps:
- http://download.oracle.com/docs/cd/B10500_01/network.920/a96580/mts.htm#447168
Cheers,
Francisco Munoz Alvarez
http://www.oraclenz.com

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Message was edited by:
Seema

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Thankx.

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Is my db using MTS or shared server?

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