Bulk Statistics Overview
Bulk Statistics are the statistics that are gathered over a given time period and written to a set of files. These statistics can be used by external analytic processes and/or network management systems. The architecture of CPS bulk statistic collection is shown below.
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The collection utility collectd is used for collecting and storing statistics from each VM. Detailed collectd documentation can be found on http://collectd.org/.
Collectd within CPS is deployed with nodes relaying data using the collectd network plug-in (https://collectd.org/wiki/index.php/Plugin:Network) to the centralized collection nodes on the pcrfclient01 and pcrfclient02 virtual machines. The centralized collector writes the collected data to output CSV files.
![]() Note |
pcrfclient01 and pcrfclient02 collect bulk statistics independently. As a result, it is normal to have slight differences between the two files. For example, pcrfclient01 generates a file at time t and pcrfclient02 generates a file at time t +/- the clock drift between the two machines. |
As a best practice, always use the bulk statistics collected from pcrfclient01. pcrfclient02 can be used as a backup if pcrfclient01 fails.
If pcrfclient01 becomes unavailable, statistics is still gathered on pcrfclient02. Statistics data is not synchronized between pcrfclient01 and pcrfclient02, so a gap exists in the collected statistics while pcrfclient01 is down.
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Statistics value in csv files is displayed in E notation format depending on value and data source type. For example, for Gauge type of data source, statistics value is converted to E notation if value is greater than 107. |