Poll strategy for server monitors

How does poll strategy setting work?

When configuring thresholds for performance metrics, you can set strategies depending on which the monitoring agent will send alerts during a threshold breach. Here are the available options:
  1. Poll count
  2. Poll average
  3. Time duration
  4. Average time
  5. Poll sum
  6. Time sum
  7. Min poll
  8. Min time
  9. Max poll
  10. Max time
  11. 95th percentile poll
  12. 95th percentile time
Notes
The default strategy option is Poll count.
Info
To make sure the condition applied on the strategy “Strategy-3: Time duration or Strategy-4: Average value during time duration” for threshold breach detection works as intended, you must ensure that you specify a time duration which is at least twice the applied check frequency for that monitor.

Poll Count

Poll count refers to the number of times Site24x7 checks the status of a resource (such as CPU usage) within a predefined period (like five minutes). If a threshold value is breached during five consecutive poll counts, a Trouble alert is sent to the users. For instance, let the threshold value of CPU usage be 70%.

By the end of the eighth poll, a Trouble alert is sent to the user.

Poll Average

During five consecutive polls, if the average CPU usage exceeds the threshold value, a Trouble alert is sent to the users.

Sum of CPU usage for the first five consecutive polls: 68+74+71+75+70 = 358
Average: (358)/5 =71.6
Since the average exceeds 70, a Trouble alert is sent to the users.

Time Duration

When CPU usage exceeds 70% within a time span of five minutes, a Trouble alert is sent. 

After the poll at 12:56am, a Trouble alert is sent to the user.

Average Time

When CPU usage exceeds an average of 70% within a time span of five minutes, a Trouble alert is sent.

Sum of CPU usage for the first five minutes: 68+74+71+75+70 = 358
Average: (358)/5 =71.6
Since the average exceeds 70, a Trouble alert is sent to the users.

Poll sum

During five consecutive polls, if the sum of failed requests exceeds a predefined value, such as 10, a Trouble alert is sent to the users.

By the end of seventh poll, the sum of failed requests for five consecutive polls is 3+2+3+1+2 = 11. So, a Trouble alert is sent.

Time sum

When the number of failed requests exceeds 10 within a predefined time span, like five minutes, Trouble alert is sent to the users. 

By 12:55am, the sum of failed requests within five minutes is 3+2+3+1+2 = 11. So, a Trouble alert is sent.

Min poll

If the lowest page view count recorded during 10 continuous polls is below the threshold, such as five, then a Trouble alert is sent to the users.

Of these recorded values (12, 15, 10, 7, 17, 20, 3, 8), the lowest is three, which is less than five. So, a Trouble alert is sent. 

Min time

If the lowest page view recorded during any polling interval within a 10-minute timeframe is less than a predefined threshold, like 5, a Trouble alert is sent to users.

Of these recorded values (7, 10, 6, 2, 8, 8, 6, 9, 10, 7), two is the lowest, which is less than five. So, a Trouble alert is sent to users. 

Max poll

If the lowest page view count recorded during 10 continuous polls is above the threshold, such as 100, then a Trouble alert is sent to the users.

Of these recorded values (94, 75, 60, 73, 67, 105, 93, 88), the highest is 105. This value is greater than 100. So, a Trouble alert is sent to the users.

Max time

If the page view count recorded during any polling interval within a 10-minute timeframe is more than a predefined threshold, like 100, a Trouble alert is sent to users.

Of these recorded values (79, 80, 65, 92, 89, 98, 76, 94, 109), the highest is 109. This is greater than 100. So, a Trouble alert is sent to the users.

95th percentile poll

For a predefined set of continuous polls, like five, if the predefined 95th percentile value, say 10, is reached, then a Trouble alert is sent.

The 95th percentile for the third poll is 10. So, a Trouble alert is sent to the users.

95th percentile time

For a predefined set of time, like 10 minutes, if the predefined 95th percentile value, say 10, is reached, then a Trouble alert is sent. 

The 95th percentile in the sixth minute is 10. So, a Trouble alert is sent to the user. 

Related article

  1. How to calculate the 95th percentile








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