Re: [hobbit] strange graph behavior - random machines & graphs

["Gary Baluha" <gumby3203 (at) gmail.com>]

On Dec 5, 2007 6:01 PM, Josh Luthman <josh (at) imaginenetworksllc.com> wrote:

> Very cool, Gary.  Awesome to the max!
>
> Thank you very much for sharing your experience and a fix!
>
> Just for the record - when using this double check the rrdtool dir and the
> user:group permissions - not everyone uses those same settings!
>

Yeah, I thought of that after I uploaded the script.  It's a simple enough
script that people can just modify the appropriate sections of code to suit
their environments.


>
> Again, thanks a lot!
>
> On 12/5/07, Gary Baluha <gumby3203 (at) gmail.com> wrote:
>
> > I wrote a script to clean up these bogus values.  Of course, if there
> > are trend graphs where numbers large enough for NNNe+1NN to be valid, the
> > script will have unexpected results.  To run the script, you need to "cd"
> > into the directory with the rrd files to be fixed.
> >
> > On Dec 5, 2007 2:05 PM, Gary Baluha < gumby3203 (at) gmail.com> wrote:
> >
> > > cd hobbit_data_dir/host_machine
> > > rrdtool dump clock.rrd > clock.xml
> > >
> > > I know any number that shows up greater than "e+1nn" is bogus, so I
> > > search for "e+1".
> > >
> > > One of several bogus data lines:
> > > <!-- 2007-11-26 19:00:00 EST / 1196121600 --> <row><v>
> > > 3.9551632477e+169 </v></row>
> > >
> > > Same line, changed to NaN (repeat for all affected lines):
> > > <!-- 2007-11-26 19:00:00 EST / 1196121600 --> <row><v> NaN </v></row>
> > >
> > > rrdtool restore clock.xml clock.rrd
> > >
> > >
> > > On Dec 5, 2007 11:57 AM, Kern, Thomas < Thomas.Kern (at) hq.doe.gov >
> > > wrote:
> > >
> > > >  Could you give a short example of a bogus and a changed (NaN)
> > > > entry, just in case that is also happening to some of my data files?
> > > >
> > > >
> > > > /Thomas Kern
> > > > /301-903-2211 (O)
> > > > /301-905-6427 (M)
> > > >
> > > >
> > > >  ------------------------------
> > > > *From:* Gary Baluha [mailto:gumby3203 (at) gmail.com ]
> > > > *Sent:* Wednesday, December 05, 2007 11:53 AM
> > > > *To:* hobbit (at) hswn.dk
> > > > *Subject:* Re: [hobbit] strange graph behavior - random machines &
> > > > graphs
> > > >
> > > > I am now completely convinced that the strange behavior of the
> > > > graphs is due to some bad data getting inserted into the .rrd database
> > > > files.  The bad data is always the same value: 5.1776682516e+170.
> > > > That's what the value looks like when you do an rrddump on the .rrd database
> > > > file.
> > > >
> > > > I still have no idea where this value is coming from, but I have at
> > > > least determined how to fix these graphs.  I'm working on a script to do
> > > > this, but for now, I manually do an rrddump of the file, change all bogus
> > > > values to NaN (basically, searching for "e+1", since none of the values I
> > > > trend generally get that large, so I know these entries are just averaged
> > > > values of correct data and the 5.17... number), and then do an
> > > > rrdrestore from the modified xml file.
> > > >
> > > > It would be nice to determine where this problem is coming from,
> > > > though.
> > > >
> > > >
> > >
> >
> > To unsubscribe from the hobbit list, send an e-mail to
> > hobbit-unsubscribe (at) hswn.dk
> >
> >
> >
>
>
> --
> Josh Luthman
> Office: 937-552-2340
> Direct: 937-552-2343
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>
> Those who don't understand UNIX are condemned to reinvent it, poorly.
> --- Henry Spencer
>