i know there are no magic formulas, but im hoping for something better than trial and error. i would assume that parallel query helps most when:
1. are doing work off of multiple mount points. 2. Have alot more LIOs to perform than PIOs(such as sorts). am i close on this? > > From: "M Rafiq" <[EMAIL PROTECTED]> > Date: 2003/09/18 Thu PM 01:34:44 EDT > To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> > Subject: Re: max parallel query > > Tanel, > You are right. There is a param parallel_automatic(I don't remember exact > name as I don't have access to database) which should be set to true and let > system decide how many pq slave to be used. For max_parallel_server default > is 5 and can be set to higher number which memory and cpu can handle. It > is faster because it uses all system resources at a given time. > > Rarallel process can be used for large batch jobs during off-peak time. > > Regards > Rafiq > > > Reply-To: [EMAIL PROTECTED] > To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> > Date: Thu, 18 Sep 2003 08:39:44 -0800 > > There is no simple magic formula how many parallel slaves you should have. > It all depends on your CPU and IO utilization. Yes, utilization, because if > your CPUs or IO are running at their limits already, you won't benefit from > parallel execution at all. In fact PX may make the situation even worse, > because it's designed to give you the results the fastest way, not the most > efficient way. > > Tanel. > > ----- Original Message ----- > To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> > Sent: Thursday, September 18, 2003 6:15 PM > > > > We run multiple instances on the same server. My understanding is > max_parallel_servers should be set to 4 x CPU. We have 4 CPUs which means > 16. > > > > however, does this take into account multiple instances on the same > server? > > > > > > -- > > Please see the official ORACLE-L FAQ: http://www.orafaq.net > > -- > > Author: <[EMAIL PROTECTED] > > INET: [EMAIL PROTECTED] > > > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > > San Diego, California -- Mailing list and web hosting services > > --------------------------------------------------------------------- > > To REMOVE yourself from this mailing list, send an E-Mail message > > to: [EMAIL PROTECTED] (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). > > > > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Tanel Poder > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (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). > > _________________________________________________________________ > Send and receive larger attachments with Hotmail Extra Storage. > http://join.msn.com/?PAGE=features/es > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: M Rafiq > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (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). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: <[EMAIL PROTECTED] INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (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).
