Re: Seq Scan: 5.0-7.3

>Hello All, > >I have two identical db's running. > >1) Online 5.07/SCO os5.04 running on a ALR 6xPPro 200 512MB ram >2) IDS 7.3/Solaris 2.6 running on Sun E3500 4x336 Ultrasparc 512MB ram > >On two identical tables with identical index's I am experiencing a performance problem with the IDS instance. > >The simple sql below run through dbaccess on both machines returns in less than 2 seconds on the Online/SCO box, and takes more than ten seconds on the IDS/Solaris box. > >select * from contest order by contest_date, contest_time> >Output from 'set explain on' reveals that they are both doing a sequential scan, and using temp space because of the order by. > >Temp space on both machines resides in the root dbspace. Both instances have plenty of space in the root dbspace. > >Why isn't IDS as fast or faster on what I would consider superior hardware for this sequential scan and order? > >I imagine in the future I will tune IDS by using the Read Ahead values, but I cannot imagine such a large discrepancy exists because I have not set those Read Ahead values. I am not sure that Read Ahead will make a huge difference. Have you tried all the permutations of UPDATE STATISTICS that are available with IDS now? What index exists on the table? Are the engines tuned with roughly the same number of buffers, etc? Get Your Private, Free Email at http://www.hotmail.com