Re: Online 7.12 Tunning

paynesys@aol.com (Paynesys) wrote: :Serafim, : : The Informix consultants that we spoke to recommend that you : have at least 1GB RAM and 4 physical CPUs to really take : advantage of ODS. Although you can run ODS 7.x on your : platform, you don't have the hardware to run it optimally. Either your Informix consultants was wide off the mark or they included some aditional caveats you forgot here. With a 400 MB database and 32 users the application would have to be very demanding on the database access side or some extreme internal processing for this not to run with very good performance on a single processor machine. We have a 1.5 GB database with demanding applications giving good performance on a Pentium 90 MHz on SCO Unix with 140 MB of memory. If the RS/6000 machine is old it may be slower than a Pentium 90. In that case a machine upgrade would be something to think about. DSA is giving excelent performance on single processor machines when the tuning is done appropriately. Others have starting giving advice on that. I would however also look at the sql level by using set explain on. In my experience this is the key area. Correct update statistics commands can do wonders. The optimiser in 7.x is so different from the 5.x one that you must expect to do some work to get your sql statement to perform their best. : Do a vmstat from the command line during peak hours. : The "po" column should be at or near 0. If not, then your : system is probably thrashing. This is a clear indication that : there is an insufficient shared memory resources. : :-Tim Nils.Myklebust@idg.no NM Data AS, P.O.Box 9090 Gronland, N-0133 Oslo, Norway My opinions are those of my company The Informix FAQ is at http://www.iiug.org