[mrtg] Correct way to do Target math?

[Ray Van Dolson]

On Wed, Jul 25, 2007 at 08:41:27AM -0600, Eric Brander wrote:
> On 7/24/07, Ray Van Dolson <rvandolson at esri.com> wrote:
> > I'm trying to generate a graph using SNMP of actual memory used on a
> > Linux system running Net-SNMP.  In theory:
> >
> >   memTotalReal.0 - memBuffer.0 - memCached.0 - memAvailReal.0
> >
> > Is the real memory available.
> 
> 
> Are you sure about that? Why would subtracting memAVAILreal from
> memTOTALreal equal the real memory available? Seems that would give
> you memory in use. But then why subtract the buffer and cached?
> 
> Maybe I don't understand those counters but that just doesn't jive in
> my brain. Also, are these really counters or are they gauges?
> 

I made a typo, this is the actual memory being _used_ not available. :)

Was hoping no one would catch it...

Ray