Re: Online 7.x on IBM uni-processor

Bill & David, What about the SINGLE_CPU_VP parameter in the onconfig file? I was told you should also set this to a 1 on a single CPU machine to reduce the number of mutex calls. Doug On 3 Sep 1997 10:43:24 -0400, ennis@ssax.com (Bill Ennis) wrote: }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