[rrd-users] Re: new log2rrd beta - handles MAX values, etc.

[Dave Plonka]

On Tue, Jun 27, 2000 at 12:00:43PM +0200, Rainer Bawidamann wrote:
<snip>
> In the rrd file every rra ends "now". So when filling the rrd file with
> the values from the log file additional values are entered for the other
> rras. I.e. the rrd file contains
>      5 min samples from now-50h    to now
>     30 min samples from now-350h   to now
>     2 hour samples from now-1550h  to now
>     1 day samples  from now-19118h to now
> 
> So there are 
> -  5 min samples for 50h    -> 600 samples
> - 30 min samples for 350h   -> 700
> - 2 hour smaples for 1550h  -> 775
> -  1 day samples for 19118h -> 796 (+14h) -> 797

OK, thanks for the explanation - I get it.
I've changed my call too RRDs::create to this:

      RRDs::create ("$file", "-b", $START, "-s", 300,
      "DS:$opt{0}:GAUGE:86400:U:U",
      "DS:$opt{1}:GAUGE:86400:U:U",
      "RRA:AVERAGE:0.5:1:600",
      "RRA:AVERAGE:0.5:6:700",
      "RRA:MAX:0.5:6:700",
      "RRA:AVERAGE:0.5:24:775",
      "RRA:MAX:0.5:24:775",
      "RRA:AVERAGE:0.5:288:797",
      "RRA:MAX:0.5:288:797");

When "UseRRDTool Yes" is specified, why does MRTG create the RRD with
this RRA?:

                  "RRA:MAX:0.5:1:600",

Won't that RRA contain the same values as the initial AVERAGE RRA, and
therfore be redundant?:

                  "RRA:AVERAGE:0.5:1:600",

> >> And what about reading a mrtg config file to look for
> >> the log files and the datasourcetype? ;-)
> > 
> > You mean look for the "gauge", "absolute", etc. options...  hmm...
> 
> And to get the names of (all) the log files ...
> 
> > I might be willing to add this - if it could be done reasonably and
> > quickly.
> 
> I think it wouldn't take much time (for me). I would take the parser out
> of mrtg and add some calls to log2rrd. Maybe I'll do it because it's
> good for 14all ;-)

OK.  If you're enthusiastic to do that it's fine with me.  Would you
rather write it as a stand-alone wrapper script which invokes log2rrd
or integrate it right into log2rrd?  If you want to do the former, I'd
like to make sure I have all the command-line options in log2rrd that
you need.  If you want to do the latter, we could synchronize a
hand-off of log2rrd (cuz I'm beta testing log2rrd-1.012) and/or keep in
touch to integrate the patches in prep for submitting a coherent
version for the RRDTOOL "contrib".

A couple other log2rrd issues:

* Are there ".log" files out there where the two `data sources' are of
  two different types (e.g. one counter and the other gauge)?  If so, I
  should modify the log2rrd command line options so that you can
  specify that.  (Right now you can just say one type, e.g.
  "-t COUNTER", "-t GAUGE", etc.)

* I think I should also modify log2rrd to change the heartbeat to 600
  after the data is inserted as well.  (Previously it was leaving it at
  86400.)  Any thoughts?

Later,
Dave

-- 
plonka at doit.wisc.edu  http://net.doit.wisc.edu/~plonka  ARS:N9HZF  Madison, WI