Re: NUMCPUVPS on a box having multiple Informix Instances

Setting MULTIPROCESSOR in a single cpu system is definitely not recommended because it creates performance problems. For a multiprocessor system with one cpu vp I am not sure. But I would rather not set it and set SINGLE_CPU_VP instead. This skips all multiprocessor latching code and is a performance gain. The drawback is that you have to reboot online to add cpu vps. Michael Murray Wood wrote: > Start with 1 CPUVP (or 2) on each instance, but with MULTIPROCESSOR set. > If/when one instance cannot keep up with the workload just add another > CPUVP. When it has settled down and you know what resource each needs, > affinitise each on their own CPU, if available on your platform. > > MW > > >>-----Original Message----- >>From: owner-informix-list@iiug.org >>[mailto:owner-informix-list@iiug.org]On Behalf Of Chavan Koya >>Sent: Friday, 30 May 2003 9:13 a.m. >>To: Jay Aymond; informix-list@iiug.org >>Subject: Re: NUMCPUVPS on a box having multiple Informix Instances >> >> >>The instances will not be too busy. The processors speed is 250MHz. >>Thank you >>Chavan Koya >> >>----- Original Message ----- >>From: "Jay Aymond" <jaymond@communitycoffee.com> >>To: <informix-list@iiug.org> >>Sent: Friday, May 23, 2003 2:59 PM >>Subject: Re: NUMCPUVPS on a box having multiple Informix Instances >> >> >> >>>It depends ... >>> >>>How busy will each of the instances be? >>> >>>Will the instances be busy at the same times? >>> >>>What is the CPU speed of the processors? On some of the >> >>faster CPU's, you >> >>>can actually get increased performance by having more that >> >>one CPU VP per >> >>>hardware CPU. >>> >>> >>>"Chavan" <chavankumar@rediffmail.com> wrote in message >>>news:a1d0bf15.0305231135.35622597@posting.google.com... >>> >>>>Hi All, >>>> The Informix recommandation for configuring >>> >>NUMCPUVPS is equal>> >>>>to, or less than the number of physical CPU's in the box. I had to >>>>configure two instances on a box, which is having 6 cpu's. So what >>>>should be the NUMCPUVPS, is it 3 for each instance or 6 >>> >>for each. For >> >>>>time being i configured it as 3 each. >>>>Any ideas, comments. Thanks in advance. >>>> >>>>Chavan Koya >>> >>> >>> > > -- === Michael Mueller ================== Tel. + 49 8171 63600 Fax. + 49 8171 63615 Web: http://www.mm.kay-mueller.de http://www.planets.kay-mueller.de ======================================