Re: how much cpu does Informix use

Hey Art, Thanks for the reply.  Please see my responses intermixed with yours. ----- Original Message ----- Subject: Re: how much cpu does Informix use Date: Thu, March 27, 2008 9:52 From: "Art S. Kagel (Oninit)" Floyd Wellershaus wrote: > > IDS10 on AIX 5.3. > > Sorry if this has been asked before, but I still don't have a > > satisfactory answer. > > We are trying to determine exactly how much percentage of our system > > cpu, that Informix is using through time. > > This is proving to be a difficult task, because sar doesn't provide > > process names or id's so that I can correlate a percentage to 'oninit'. > > ps command doesn't provide percentage. > > Sounds like what you want is 'top'. You should be able to get an AIX > specific executable from IBM and IB that IBM also has an enhanced > version of top for AIX called 'topas' or download the generic UNIX top > source from sourceforge or www.unixtop.org. We have topas, but I am unable to make it provide the information for all oninit processes. It seems to only care about the top 10 or so processes. > > > > > I am thinking that at least I can use onstat -g glo, add up all of the > > total time for cpu vps ( because I think those are the metrics of what > > oninit does on the physical cpus ). > > > > First question: Am I correct that only the cpuvps are directly tied to > > the physical cpus? Or do I need to be counting all of the vps ? > > That depends. If you are using a version before 9.40 (don't remember > your specs Floyd - sorry) that's certainly true, the AFF* parameters > only affect CPU VPs. In 9.40 and later if you are using VPCLASS to > specify VP settings (rather than the vp class specific parameters like > NUMAIOVPS) you can set affinity for any VP class that can be configured > using the VPCLASS parameter. > Not sure I get what you're saying. So we don't define VPCLASS, we just have NUMPAOVPS, NUMCPUVPS etc.... So does that mean we do count the aiovp stats when adding up the "physical" cpu time ?   What about Soc, lio etc... , or just CPUVP'S ? > > > > Second question. The numbers provided for each cpu is what ? Seconds ? > > Yes. > > > So, assuming that oninit has been up the entire time that the lpar has > > been up, if I divide the total time from onstat -g glo by the number > > of seconds since the lpar has been up, will that tell me the > > percentage of cpu that oninit uses ? > > Yes. That would be percent of available CPU if you add up all of the > CPU times for all VPs (or for given classes of VPs) and divide that by > the number of CPU Cores available to the instance time seconds since the > IDS instance was started that would give the percent of total CPU time > used. If you only multiply by the number of CPUs to which the VPs were > affined that would give the percentage of available assigned CPU time used. > Again, I need more clarity on this. We aren't using any processor affinity. Say I have 2 cpuvps that are up for one day ( 86400 seconds ). Say the total time for both of them comes to 43200 seconds. If I have 2 physical cpus on the machine, does that mean informix used 50% of available cpu or 25% ? Thanks !! > > Thanks for any advice on this. > > > > Floyd > Art S. Kagel > Oninit > > > > > ------------------------------------------------------------------------ > > > > _______________________________________________ > > Informix-list mailing list > > Informix-list@iiug.org > > http://www.iiug.org/mailman/listinfo/informix-list > > > > >