[rrd-users] RRD graph start at arbitrary time

[Tim Niemueller]

Dear RRD users.

I'm trying to graph MongoDB operation counters that I have recorded. In
particular, I want to graph the data of a specific experiment which
lasted for about two hours and for which I have data with a 10 sec step
time.

The definition of the RRAs is the one at
http://git.fawkesrobotics.org/fawkes.git/blob/HEAD:/src/plugins/rrd/aspect/rrd_descriptions.cpp#l341.
The particular data file I'm using is at
https://docs.google.com/file/d/0ByHokBJFy8hPeGFEZWh0NjJVajg/edit?usp=sharing.

The script I'm using to create the graph is this:

--- 8< ---
START_TIME="20130801 14\\:50"
IMG_FORMAT="PDF"
IMG_EXT="pdf"

rrdtool graph "opcounters.$IMG_EXT" --imgformat="$IMG_FORMAT" \
        --start="$START_TIME" --end="start+60m" --step=10 \
        --disable-rrdtool-tag --width=622 \
        --font "LEGEND:10:" --font "UNIT:10:" \
        --font "TITLE:12:" --font "AXIS:8:" \
        --title="MongoDB Op Counters (Averages)" \
        --vertical-label="Ops/sec" \
        --pango-markup \
        --grid-dash 1:2 --color "GRID#BBBBBBC4" \
        "DEF:insert=opcounters.rrd:insert:AVERAGE:" \
        "DEF:query=opcounters.rrd:query:AVERAGE:" \
        "DEF:update=opcounters.rrd:update:AVERAGE:" \
        "DEF:delete=opcounters.rrd:delete:AVERAGE:" \
        "DEF:getmore=opcounters.rrd:getmore:AVERAGE:" \
        "DEF:command=opcounters.rrd:command:AVERAGE:" \
        "CDEF:insert_ps=insert,10,/" \
        "CDEF:query_ps=query,10,/" \
        "CDEF:update_ps=update,10,/" \
        "CDEF:delete_ps=delete,10,/" \
        "CDEF:getmore_ps=getmore,10,/" \
        "CDEF:command_ps=command,10,/" \
        "COMMENT:     " \
        "LINE1.5:insert_ps#FF7200:Inserts" \
        "GPRINT:insert_ps:AVERAGE:%6.2lf %s" \
        "LINE1.5:query_ps#503001:Queries" \
        "GPRINT:query_ps:AVERAGE: %6.2lf %s" \
        "LINE1.5:update_ps#EDAC00:Updates" \
        "GPRINT:update_ps:AVERAGE: %6.2lf %s\\n" \
        "COMMENT:     " \
        "LINE1.5:delete_ps#506101:Deletes" \
        "GPRINT:delete_ps:AVERAGE:%6.2lf %s" \
        "LINE1.5:getmore_ps#0CCCCC:Getmores" \
        "GPRINT:getmore_ps:AVERAGE:%6.2lf %s" \
        "LINE1.5:command_ps#53CA05:Commands" \
        "GPRINT:command_ps:AVERAGE:%6.2lf %s\\n" \
--- 8< ---

As you can see I'm trying to graph starting at 14:50 for two hours. I
have confirmed that data is available from 14:53 to 16:49 at the given
date at 10sec steps in the data file (via rrdtool dump). But the graph
will always start at 14:00 and I have run out of ideas what to try next.

Is there a way to force RRDtool to start at an arbitrary time of my
choosing, or can someone point me to the part in the source code that I
need to mangle to make it do what I want?

That would be highly appreciated!

Regards from Aachen,
  Tim

-- 
KBSG - Knowledge-based Systems Group            AllemaniACs RoboCup Team
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