Re: how much cpu does Informix use
Posted in 2008
Thanks Keith,
That reminds me, I think I have hit youall up with this issue before. I
have been messing with a version of nmon, and am still unable to get it to
provide what I need. I'll take a look some more at it.
----- Original Message -----
Subject: Re: how much cpu does Informix use
Date: Thu, March 27, 2008 10:22
From: "Keith Simmons" <smiley73@googlemail.com>
On 27/03/2008, Art S. Kagel (Oninit) <art@oninit.com> wrote:
> > 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.
> >
> > >
> > > 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.
> >
> > >
> > > 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.
> >
> > >
> > > 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
> > >
> >
> >
> > _______________________________________________
> > Informix-list mailing list
> > Informix-list@iiug.org
> > http://www.iiug.org/mailman/listinfo/informix-list
> >
> Floyd
>
> topas is part of the AIX O/S and will give you some info, also nmon
> (included in the O/S but recommended that you download the latest
> version from IBM) is probably better as it gives the option of
> capturing data over time and importing into a spreadsheet (excel).
>
> Keith
>
>