Sizing tables

Use these tables to help determine the appropriate polling load for your system, in particular, how many entities and KPIs you should be polling and what polling interval to set for your poll policies.

Use the following table to determine your approximate polling insert rate and the number of rows this insert rate will generate in each of the historical poll data tables. Use these tables by reviewing the following columns and finding values that most closely match the settings in your network:

In each of the examples presented in the table, the number of KPIs (poll definitions) per poll policy and the poll interval for each poll policy are assumed to be the following:

Table 1. Number of KPIs and poll interval per poll policy
	Number of KPIs	Poll interval in minutes	Number of polls per hour
Chassis polls	3	5	36
Interface polls	5	5	60

The following examples show how the values for insert rate and number of rows in the historical poll data tables change as you vary the number of polled entities in your network.

Example that falls within the recommended limits

The following examples fall within the recommended limits for a stable polling system.

Number of polled entities

Chassis devices: 15,000
Interfaces: 300,000

Table 2. Insert rate and number of rows in millions per historical poll data table
	Insert rate [Inserts/hour]	Last day [Millions of rows]	Last week [Millions of rows]	Last month [Millions of rows]	Last year [Millions of rows]
Chassis polls	0.72	5.76	5.04	5.4	5.475
Interface polls	18.56	153.6	134.4	144	146
Total	19.28	159.36	139.44	149.4	151.475

Example that falls outside of the recommended limits

The following examples fall outside of the recommended limits for a stable polling system.

Number of polled entities

Chassis devices: 30,000
Interfaces: 500,000

Table 3. Insert rate and number of rows in millions per historical poll data table
	Insert rate [Inserts/hour]	Last day [Millions of rows]	Last week [Millions of rows]	Last month [Millions of rows]	Last year [Millions of rows]
Chassis polls	1,080,000	8.64	30.24	32.4	32.85
Interface polls	30,000,000	240	840	900	912.5
Total	31,080,000	248.64	870.24	932.4	945.35

Try it for yourself

Use the spreadsheet calculator available on SMC to estimate these values:

Estimated number of polled entities in your network
Average number of KPIs and poll interval across your poll policies

The spreadsheet calculates the insert rate and number of rows in the historical poll data tables for your network based on your estimated values.