RE: NUMCPUVPS question

Doug This is a "it depends upon what else is running on your server" question. If NUMCPUVPS is the number of CPU's, then it is possible that Informix could gain short term control of all CPU's, starving other processes (particularly OS) on the system. If you have 2-4 CPU's then this may be necessary so your application runs in a timely manner - your application is waiting for resource which is available because CPu is free but no CPUVP to run it. It is not recommended with 4 or more CPU's, but may be appropriate to do in certain circumstances. If it is available you should affinitise CPUVPS to specific CPU's. This stops the OS from context switching the CPUVP since each must always run on a specific CPU! Informix schedules the load betwen the CPUVPS. Murray Wood -----Original Message----- From: Doug Agnew [SMTP:dagnew@charlottepipe.com] Sent: Wednesday, June 30, 1999 8:04 AM To: informix-list@iiug.org Subject: NUMCPUVPS question Simple question, but possibly an answer to our performance problems: What would be the possible effects of having NUMCPUVPS equal the number of physical CPUs in a database server?? I contend that this would cause the other oninit processes (the server side of the connected clients) to hang ready waiting for a cpu to become available. Since the CPU VPs are context-switching between other VPs without relinquishing control, then the client pieces would get very little process time and the cpu load could build up and user response time would suffer. Am I close, off base, or what?? Thanks in advance, Doug Agnew dagnew@charlottepipe.com