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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Since your first RRA has a count of 1, then 1cdp = 1pdp = 15min. There are 96 rows, and so (as you say) this RRA has a length of 96x15min = 1 day.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Your second RRA has a count of 4, so 1cdp = 4pdp = 1hour. There are 24 rows, so it also has a length of 1 day (in which case it is likely not necessary).<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Probably, you want to make these RRA much longer; 2880 rows in the first RRA will be about 30 days long.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If your metrics are all coming in the same file, for the same point in time, and all being pushed into the RRD at the same time, then it makes sense to have a single RRD to hold them as in your example. You would usually use a separate RRD if the data came separately, potentially for different times. Then separate RRD would make sense as you may get one sample but not another, or they were sampled at differing times.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>However, in your example, your TapeRate and DASDRate variables have been given a valid range of 0 – 100. This makes sense if they are a percentage, but not if they are data rates which could be larger than 100B/s. You may want to make the upper bound on these DS higher or undefined. Also, if you can extract a data counter rather than a rate, you will get more accurate results overall by using this with a DS type of ‘counter’ and allowing RRDTool to calculate the rate.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Steve<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Steve Shipway<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>s.shipway@auckland.ac.nz<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> stevensim@principal-systems.com [mailto:stevensim@principal-systems.com] <b>On Behalf Of </b>Steven Sim<br><b>Sent:</b> Tuesday, 10 June 2014 12:57 p.m.<br><b>To:</b> Steve Shipway<br><b>Cc:</b> rrd-users@lists.oetiker.ch<br><b>Subject:</b> Re: [rrd-users] If input is already in text format and I craft a perl script to parse the text format and update rrd database, what should the step and heartbeat be?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Steve;<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Firstly, thanks deeply for replying!<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I do have the sample times in my file and this can be easily converted to epoch time using perl for each data point.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Two more questions;<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>The data measures mainframe CPU Busy and other metrics, much like Solaris <span style='font-family:"Courier New"'>prstat</span> or Linux <span style='font-family:"Courier New"'>top</span> command with each data point 15 minutes apart.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I've created a database like so ...<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><span style='font-family:"Courier New"'>rrdtool create ${RRDBfile} \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> --step 900 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> --start ${STARTIME} \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> DS:CPUBusy:GAUGE:1800:0:100 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> RRA:AVERAGE:0.5:1:96 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> RRA:AVERAGE:0.5:4:24 \</span><o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>The <span style='font-family:"Courier New"'>${STARTIME}</span> variable is calculated as the first sample time minus 900 seconds.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>The first RRA archive is 1 PDP with 96 CDP or 24 hours. Is my understanding correct?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>(Since 1 PDP = 15 minutes, 96 CDP will be 15 minutes * 96 or 24 hours)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>So if I wish to store for a month, then i do<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'>RRA:AVERAGE:0.5:1:2880 ??</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>As for the other metrics, like Tape Rate, DASD Rate, can I storage them in a single RRD database or would you recommend I create a database each for each metric?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>For example, my understanding for a multi metric database creation would be ..<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><span style='font-family:"Courier New"'>rrdtool create ${RRDBfile} \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> --step 900 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> --start ${STARTIME} \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> DS:CPUBusy:GAUGE:1800:0:100 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> DS:DASDRate:GAUGE:1800:0:100 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> DS:TAPERate:GAUGE:1800:0:100 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> RRA:AVERAGE:0.5:1:96 \</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> RRA:AVERAGE:0.5:4:24 \</span><o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Would the above understanding be correct?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Deepest Regards<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>Steven Sim<o:p></o:p></p><div><p class=MsoNormal>On Tue, Jun 10, 2014 at 6:22 AM, Steve Shipway <<a href="mailto:s.shipway@auckland.ac.nz" target="_blank">s.shipway@auckland.ac.nz</a>> wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If the readings are taken at 15min intervals, then your step should be 15min (900s), because this is the step between samples.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Generally speaking, unless you have a special case, you should set your heartbeat to be twice your step – in this case, 1800s</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>When you update your RRDtool database, you will give RRDTool a point in time and the data to store at that point in time. DO NOT use ‘N’ (‘now’) for your point in time as you should be specifying the point in time when the data were sampled, not when you store them. The step and heartbeat apply to the data point in time, not when you happen to store them.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Obviously, you need to have the sample times in your text file. If you do not have them, you may be able to deduce the time by knowing that they are 15min apart and extrapolating?</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Steve</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Steve Shipway</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="mailto:s.shipway@auckland.ac.nz" target="_blank">s.shipway@auckland.ac.nz</a></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> rrd-users-bounces+s.shipway=<a href="mailto:auckland.ac.nz@lists.oetiker.ch" target="_blank">auckland.ac.nz@lists.oetiker.ch</a> [mailto:<a href="mailto:rrd-users-bounces%2Bs.shipway" target="_blank">rrd-users-bounces+s.shipway</a>=<a href="mailto:auckland.ac.nz@lists.oetiker.ch" target="_blank">auckland.ac.nz@lists.oetiker.ch</a>] <b>On Behalf Of </b>Steven Sim<br><b>Sent:</b> Tuesday, 10 June 2014 3:12 a.m.<br><b>To:</b> <a href="mailto:rrd-users@lists.oetiker.ch" target="_blank">rrd-users@lists.oetiker.ch</a><br><b>Subject:</b> [rrd-users] If input is already in text format and I craft a perl script to parse the text format and update rrd database, what should the step and heartbeat be?</span><o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hello;<o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>my sensor tech staff has collated the readings onto several text files, each reading 15 minutes apart.<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I have crafted a Perl script to parse the text file and execute rrdtool update for each reading in the text file.<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>In this case, what should be my step and heartbeat?<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>The actual readings are taken 15 minutes apart, but the actual feeding into the rrdtool database are actually loops through the perl script, each update at most a second or less apart<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Do i still retain step=15 minutes and heartbeat=15 minutes x 2 ?<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Deepest Regards<br>Steven Sim<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div></div></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>