RE: PDQ on 7.12

}---------- }From: barryleb@atl.mindspring.com[SMTP:barryleb@atl.mindspring.com] }Sent: Wednesday, August 07, 1996 3:20 PM }To: informix-list@rmy.emory.edu }Subject: Re: PDQ on 7.12 } }TASHKOP@kiwi.co.nz (Peter Tashkoff) wrote: } }>Morning all }>We are considering enabling PDQ on DSA }>7.12/Solaris 2.4. }>We had previously disabled this facility due to the }>bug in 7.10 where it didn't handle the lower level }>threads. }>So... we are seeking comfort from people that might }>already be running PDQ enabled over 7.12 or later. }>Does it work OK now? Are there any pitfalls or }>caveats? }>Thanks in advance }>-- }>-- }>Peter Tashkoff }>NZ Kiwifruit Project Consultant/DBA }>Marketing Board. Standard Disclaimers apply }>This posting may not be used by any commercial }>organisation to vilify another. } }We are currently using PDQ=2 using 7.13.uc2 on Solaris 2.4. We have }had no problems with this version. We also set PDQ=20 on some simple }apps and have even used a setting of 100. } }We have been on 7.13 for 1 1/2 months. We used the same setting for 6 }months on version 7.11.uc1. Again no problems. } }We had all kinds of problems on 7.10.uc1 and ud1 with performance and }PDQ made no difference. In general, I'd say they solved these poblems. } }We have seen problems with the OPTCOMPIND settings and are currently }using a value of 0 to eliminate Dynamic Hash joins. But, that's }another story. } }Oh yeah, we are primarily a DSS environment with very little OLTP. }Hope this helps. } We are running 712UC2, on a dual proc. HP model K w/512MB RAM. What a nightmare. PDQ is useless, and OPTCOMPIND is turned off. If we edit a table structure while someone is in the table, we crash the database, and afterwards, about 50% of the time, it will set everyones PDQ to 100. Needless to say this doesn't last very long, before half our users get locked out. The only way we found to fix this is to set the MAXPDQ to 0. Which is now where we leave it. Setting the PDQ even when it 'works', causes the resources to be dedicated to the one job running with PDQ (no matter what it is set at). I certainly can't say whether your PDQ will work, but be prepared. ...Michael... }DART, Inc.