RE: Rollback Segments on 8.1.7.4
I will have to check your question on 'fewer sorts'. As far as changes to the SQL statements, there were 1 or 2 sql statements changed in the application because they no longer worked efficiently with the change to 8.1.7. But, on the whole (lets say 98%+ of the time) no changes were made. -Original Message- Sent: Monday, March 10, 2003 5:39 PM To: Multiple recipients of list ORACLE-L Did any of the rollback segment storage parameters (i.e. INITIAL, NEXT, PCTINCREASE, MINEXTENTS, MAXEXTENTS, OPTIMAL) or the number of rollback segments change between 8.0.5 and 8.1.7? Changes to any of these variables could impact the space available for storing inactive undo blocks for read-consistency purposes. If the answer is of course not, then here comes the harder question: did the SQL statements change between 8.0.5 and 8.1.7? Not just outright different SQL statements, but even the same SQL statements running with different execution plans? For example, changing explain plans so that SORT-MERGE join is no longer use could have significant impact on ORA-01555, as forcing sorts are one way to minimize SNAPSHOT TOO OLD. Having queries run faster is another way to minimize ORA-01555, so getting rid of SORT-MERGE joins will likely help, but if the performance improvements aren't good enough, then the conversion to HASH or NESTED LOOP joins may allow more ORA-01555 to occur. Have you noticed fewer sorts occurring since 8.0.5? Just some ideas... - Original Message - To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED] Sent: Monday, March 10, 2003 2:59 PM Evening; Has anyone noticed any difference on the way Oracle uses Rollback Segments on 8.1.7.4 versus 8.0.5 ?? Ever since upgrading to 8.1.7.4 from 8.0.5 on our Solaris servers we have noticed more SNAPSHOT TOO OLD errors than we used to. Are there any suggestions as to rollback tuning that has to be done with that kind of version move ?? Any help would be appreciated. Thanks Kevin -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Kevin Lange 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: Tim Gorman 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: Kevin Lange 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).
RE: Rollback Segments on 8.1.7.4
Dan; Everything remained the same on the DB except the version. No changes made. -Original Message- Sent: Monday, March 10, 2003 5:34 PM To: Multiple recipients of list ORACLE-L Kevin, The ORA-01555 errors are almost certainly symptoms, not the actual problem. It has been a few years since I tested an 8.0.x db, but I do not recall seeing any changes in rollback segments from 7.3 to 8.1. Have you converted from Dictionary to Locally managed RBS tablespaces? When you upgraded, did you change any of the settings, like OPTIMAL, for the rollback segments? Were they dropped and recreated or upgraded inline? -- Daniel W. Fink http://www.optimaldba.com IOUG-A Live! April 27 - May 1, 2003 Orlando, FL Sunday, April 27 8:30am - 4:30pm - Problem Solving with Oracle 9i SQL Wednesday, May 1 1:00pm - 2:00pm - Automatic Undo Internals Kevin Lange wrote: Evening; Has anyone noticed any difference on the way Oracle uses Rollback Segments on 8.1.7.4 versus 8.0.5 ?? Ever since upgrading to 8.1.7.4 from 8.0.5 on our Solaris servers we have noticed more SNAPSHOT TOO OLD errors than we used to. Are there any suggestions as to rollback tuning that has to be done with that kind of version move ?? Any help would be appreciated. Thanks Kevin -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Daniel W. Fink 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: Kevin Lange 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).
Rollback Segments on 8.1.7.4
Evening; Has anyone noticed any difference on the way Oracle uses Rollback Segments on 8.1.7.4 versus 8.0.5 ?? Ever since upgrading to 8.1.7.4 from 8.0.5 on our Solaris servers we have noticed more SNAPSHOT TOO OLD errors than we used to. Are there any suggestions as to rollback tuning that has to be done with that kind of version move ?? Any help would be appreciated. Thanks Kevin -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Kevin Lange 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).
Re: Rollback Segments on 8.1.7.4
Kevin, The ORA-01555 errors are almost certainly symptoms, not the actual problem. It has been a few years since I tested an 8.0.x db, but I do not recall seeing any changes in rollback segments from 7.3 to 8.1. Have you converted from Dictionary to Locally managed RBS tablespaces? When you upgraded, did you change any of the settings, like OPTIMAL, for the rollback segments? Were they dropped and recreated or upgraded inline? -- Daniel W. Fink http://www.optimaldba.com IOUG-A Live! April 27 - May 1, 2003 Orlando, FL Sunday, April 27 8:30am - 4:30pm - Problem Solving with Oracle 9i SQL Wednesday, May 1 1:00pm - 2:00pm - Automatic Undo Internals Kevin Lange wrote: Evening; Has anyone noticed any difference on the way Oracle uses Rollback Segments on 8.1.7.4 versus 8.0.5 ?? Ever since upgrading to 8.1.7.4 from 8.0.5 on our Solaris servers we have noticed more SNAPSHOT TOO OLD errors than we used to. Are there any suggestions as to rollback tuning that has to be done with that kind of version move ?? Any help would be appreciated. Thanks Kevin -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Daniel W. Fink 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).
Re: Rollback Segments on 8.1.7.4
Did any of the rollback segment storage parameters (i.e. INITIAL, NEXT, PCTINCREASE, MINEXTENTS, MAXEXTENTS, OPTIMAL) or the number of rollback segments change between 8.0.5 and 8.1.7? Changes to any of these variables could impact the space available for storing inactive undo blocks for read-consistency purposes. If the answer is of course not, then here comes the harder question: did the SQL statements change between 8.0.5 and 8.1.7? Not just outright different SQL statements, but even the same SQL statements running with different execution plans? For example, changing explain plans so that SORT-MERGE join is no longer use could have significant impact on ORA-01555, as forcing sorts are one way to minimize SNAPSHOT TOO OLD. Having queries run faster is another way to minimize ORA-01555, so getting rid of SORT-MERGE joins will likely help, but if the performance improvements aren't good enough, then the conversion to HASH or NESTED LOOP joins may allow more ORA-01555 to occur. Have you noticed fewer sorts occurring since 8.0.5? Just some ideas... - Original Message - To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED] Sent: Monday, March 10, 2003 2:59 PM Evening; Has anyone noticed any difference on the way Oracle uses Rollback Segments on 8.1.7.4 versus 8.0.5 ?? Ever since upgrading to 8.1.7.4 from 8.0.5 on our Solaris servers we have noticed more SNAPSHOT TOO OLD errors than we used to. Are there any suggestions as to rollback tuning that has to be done with that kind of version move ?? Any help would be appreciated. Thanks Kevin -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Kevin Lange 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: Tim Gorman 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).
