This question comes up fairly often. You _cannot_ see exact values in RRD - it stores 'smoothed', interpolated values, not the raw data.
This is ideal and correct when monitoring trends, especially for the reason you identify - the collection periods are never exactly 5 min. The smoothing is perfect for that purpose. CW -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Pavleck, Jeremy D. Sent: Monday, May 08, 2006 2:12 PM To: [email protected] Subject: [rrd-users] Re: Precise Value Graphing Help Needed Greetings Kevin, Although I can't help you with this issue, we're also using Weblogic and would love to see the scripts you've written to automate WLShell. Currently, we're polling those stats via SNMPd, but I'd love to have access to more information provided by WLSHell. Jeremy Jeremy Pavleck Network Engineer - Systems Management IT Networks and Infrastructure Direct Line: 612-977-5881 Toll Free: 1-888-CAPELLA ext. 5881 Fax: 612-977-5053 E-mail: [EMAIL PROTECTED] Capella University 225 South 6th Street, 9th Floor Minneapolis, MN 55402 www.capella.edu -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kevin Elliott Sent: Monday, May 08, 2006 3:25 PM To: [email protected] Subject: [rrd-users] Precise Value Graphing Help Needed Greetings fellow RRDTool users, I am writing today in an attempt to diagnose why I am unable to properly visualize exact last data (using GAUGE) in my rrdtool based historic tracking instead of what appears to be averaging of some sort. WebLogic JDBC and Thread Pool Counts are the nature of our data. We are retrieving this information from production WL servers using WLShell, a java-based "shell" to WebLogic. We are creating an instance of our custom wlshell script, and using a loop inside to generate data for 5 minute intervals. After data is retrieved, the wlshell script calls a perl script that uses RRDTool libraries to update the rrd. Since the connection to the production servers over our VPN seems to vary in latency all the time, the time it takes to retrieve the data we're requesting can change, so the 5 minute intervals are more than likely not exact. My problem is that we're trying to see exact values at any given point in time (and atleast for the last 28 hours graph), rather than any sort of averaging. It is important to us that we know that around 11:05am, there was a spike of 10 connections, versus some average that says 6.7. We are seeing all sorts of decimals, and not whole integers as expected. Our perl script contains the code to create the RRD, and we're using something like: if ( ! -f $rrdfilename ) { print "WARN: RRD file ($rrdfilename) not present, creating...\n"; @rrdCreateArgs = ($rrdfilename, "-s", int($rrdInterval * 60)); if (($rrdHeartBeat = int($rrdInterval * 60) *2) < 600) { $rrdHeartBeat = 600; } foreach $iterator (0 .. $#FIELDS) { push @rrdCreateArgs, "DS:" . $FIELDS[$iterator] . ":$rrdDSType:300:-1:$rrdDSTypeMaxVal"; } push @rrdCreateArgs, "RRA:LAST:0.5:1:800"; push @rrdCreateArgs, "RRA:LAST:0.5:12:800"; push @rrdCreateArgs, "RRA:LAST:0.5:264:800"; print "Creating RRDfile \"$rrdfilename\" with create string = |" . join('\n',@rrdCreateArgs) . "|\n"; RRDs::create(@rrdCreateArgs); my $error = RRDs::error(); if ($error) { die "ERROR: Cannot create RRDfile \"$rrdfilename\", error = $error\n"; } } Our step size is 300. Instead of seeing values of 1 on the rrdgraph, we're seeing 0.2, and 0.6, etc. Some values do seem to have a plot of 2, but only because they are consistently at the value of 2, and don't vary as often. All datasources are type GAUGE. Are there any recommendations for plotting unaveraged precise at-the-moment data? I just want to plot values at 5 minute intervals that go up and down per interval. We seem to have exhausted the documentation, and have search the web for similar strategies. I think we're still not grasping the proper way to do this. Sincerest Regards, Kevin Kevin Elliott DHAP Digital, Inc -- Unsubscribe mailto:[EMAIL PROTECTED] Help mailto:[EMAIL PROTECTED] Archive http://lists.ee.ethz.ch/rrd-users WebAdmin http://lists.ee.ethz.ch/lsg2.cgi -- Unsubscribe mailto:[EMAIL PROTECTED] Help mailto:[EMAIL PROTECTED] Archive http://lists.ee.ethz.ch/rrd-users WebAdmin http://lists.ee.ethz.ch/lsg2.cgi -- Unsubscribe mailto:[EMAIL PROTECTED] Help mailto:[EMAIL PROTECTED] Archive http://lists.ee.ethz.ch/rrd-users WebAdmin http://lists.ee.ethz.ch/lsg2.cgi
