Hi I have this exact issue myself, I think I've solved it by using the following,
The Magical 0.125 I'm not sure were this comes from I've seen this around a few places and had simular results as yourself, the scale has to be calculated on the sample time your doing Sample (divide by) timeinseconds x 8 (bits) = yourscale For example, I'm doing 3 second samples so I worked out my scale like this 1 / 3 = 0.3333333333333333 * 8 = 2.666666666666667 Here is snapshot of one part of my url alias(scale(nonNegativeDerivative(s3_sw1.snmp.if_octets-GigabitEthernet_0_1.rx),2.666666666666667),'RX') Also keep in mind you need to setup your whisper storage-schemas.conf as well to expect your data every x seconds this is why I used the prefix "s3_" eg, [real_time_3s_120days] pattern = s3.* retentions = 3s:120d Hope this helps :) Regards, Quenten -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of David Michael Pennington Sent: Monday, 10 September 2012 9:01 PM To: [email protected] Subject: [Graphite-dev] [Question #208167]: Graphite SNMP Counter transforms New question #208167 on Graphite: https://answers.launchpad.net/graphite/+question/208167 I'm using graphite version 0.9.10 to read ifHCInOctets and ifHCOutOctets, which I'm polling with the collectd snmp and graphite_write plugins; I'm using collectd version 5.1.0. Data arrives into graphite with no problems; however, I want to graph as bits-per-second. To test whether my stats are correct, I started a CD iso download and watched the download rate... it varied between 1.0Mbps and 2.0Mbps. Common-sense tells you that you need to multiply Octets counters by 8 to get bits; however, it seems that I need to divide by 8 to make graphite display correctly. When I multiply by a 0.125 scale factor, "scale(scaleToSeconds(nonNegativeDerivative(<SERIES>), 60),0.125), the formula correctly converts to bits-per-second and I see numbers between 1Mpbs and 2Mbps... When I use a scale-factor of 8, it fails spectacularly; I get readings of 120Mbps, but I know that's impossible because my circuit is capped at 5Mpbs. I posted the gory-details (including config files and graph snapshots) here: http://serverfault.com/questions/425828/graphite-snmp-counter-transforms Could someone me understand the math such that scale(<series>, 8) fails? -- You received this question notification because you are a member of graphite-dev, which is an answer contact for Graphite. _______________________________________________ Mailing list: https://launchpad.net/~graphite-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~graphite-dev More help : https://help.launchpad.net/ListHelp _______________________________________________ Mailing list: https://launchpad.net/~graphite-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~graphite-dev More help : https://help.launchpad.net/ListHelp
