RE: need performance help: avoid starvation of short queries by l

Check out PDQ in the Admin Guide... ================================ Paul A. Mosser, Open Systems DBA Informix Certified DBSA Wells Fargo & Co. Tempe, Arizona paul.mosser@wellsfargo.com ================================ > -----Original Message----- > From: Dean Thompson [mailto:dean@ligonier.com] > Sent: Saturday, October 03, 1998 7:10 AM > To: informix-list@iiug.org > Subject: need performance help: avoid starvation of short queries by > long-running queries > > > We are running Informix Online on a 4-processor HP machine. > Our application > uses primarily short update transactions and short queries, > but some user > requests can generate queries that retrieve thousands of records. Our > problem is that each long-running query appears to > (approximately) consume a > processor until it completes. If four long-running queries > happen to end up > running simultaneously, then every newly-arriving short query > appears to > starve until one of the long-running queries completes and frees up a > processor. > > I would have assumed that preventing long-running queries > from starving > short ones would have been a basic Informix design issue, and > that Informix > would use a fair enough scheduling algorithm to avoid this. > Obviously we > must also consider lock conflicts, but if only three > processors are consumed > by long-running queries then short queries still complete. I > am inclined to > believe that we are overlooking a configuration or query-design issue. > > Can anyone help or at least provide insight? > > Dean Thompson > DXI > dean@ligonier.com > > > >