Re: Online 7.x on IBM uni-processor

Informix version 7 and later is multi-threaded; whch means that it can take advantage of multiprocessing. If you only have one processor you do not want to use the multiprocessing capabilities. There is overhead involved with multi-threading an operation since the threads will need to communicate with each other in order to get the job done. Informix recommends that you not use multi-processor mode until you have a machine that has at least 4 processors. The parameter in the onconfig file you need to be concerned with is MULTIPROCESSOR (set it to 0). You should also set NUMCPUVPS=1. I would think that you would expect a multi-processor machine to perform better than a single CPU machine so I wouldn't call that performance degradation. -Bill > > We are running Informix systems on IBM RS6000s under AIX 4.2. We have to > upgrade to Informix DSA v7.x to take advantage of the latest release of > our application. > > We have heard that DSA, written for multi-processors, runs slower on a > uni-processor (which is what we have). Has anyone any information on > any potential performance degradation? > > David Kerslake > > > -- Bill Ennis Voice: 312-474-7516 SSA Fax: 312-474-7460 500 W. Madison email: ennis@ssax.com ennis@accesschicago.net