RE: DS_NONPDQ_QUERY_MEM

Posted in 2008

Goldrick, Jim — Thu, 10 Jan 2008 13:05:45 -0600 — source: Usenet: comp.databases.informix

Thanks, Art. I'm confused. That seems like a very little amount to use for those types of queries (in our case, 25% of 768KB). I mean, if we are OLTP, should I then allocate more memory to PDQ so I can allocate some of that to these types of queries? I read that for OLTP you should allocate to buffers, not PDQ. Thank you, Jim Goldrick Judson University 1151 North State Street Elgin, Illinois 60123 573-332-7739 http://www.judsonu.edu jgoldrick@judsonu.edu -----Original Message----- From: Art S. Kagel (Oninit LLC) [mailto:art@oninit.com] Sent: Thursday, January 10, 2008 12:32 PM To: Goldrick, Jim Cc: informix-list@iiug.org Subject: Re: DS_NONPDQ_QUERY_MEM Goldrick, Jim wrote: > Ok, I have looked and looked and cannot find a decent, somewhat short > answer. We just upgraded to HPUX 11.23 and Informix 10.0. I have been > looking at tuning presentations, pdf files, etc online for 10.0. I keep > seeing reference to DS_NONPDQ_QUERY_MEM to help improve performance for > sorts. We are mostly an OLTP, so I have never looked at PDQ. Right now > it is set to 768KB. > OK, so before DS_NONPDQ_QUERY_MEM only a small fixed amount of memory was available for calculating aggregate function results, GROUP by and ORDER by sorts and for indec builds if PDQPRIORITY was not set or set to zero. That varied from version to version from 15KB to 50 MB. Now with this new parameter you can allocate up to 25% of PDQ.MGM memory for these queries. That means fewer will have to write to temp disk space and will run faster. Art S. Kagel Oninit > So, I am curious as to how this DS_NONPDQ_QUERY_MEM might improve our > performance, if I need to worry about it since we are OLTP, and how, if > any, allotting more resources to PDQ might help. We also run an apache > server on the same machine and client software for data entry (we're a > small university, so data entry for student courses, registration, > financials, etc). > > Thanks much, > > jim > _______________________________________________ > Informix-list mailing list > Informix-list@iiug.org > http://www.iiug.org/mailman/listinfo/informix-list > >