Modify Metric Polling Timing

You can modify metrics timing and reporting defaults.

When using the default CloudWatch properties, metrics reporting can take around 15 minutes:
  1. 5 minutes to receive a sensor data point for an instance.
  2. 5 more minutes to receive a second sensor data point for an instance.
  3. 1 more minute to calculate the difference between these two and send a single data point to CloudWatch.
  4. 1 more minute for CloudWatch to put the data in the database, making it available for a euwatch-get-stats call.
  5. 5 more minutes for euwatch-list-metrics info to be available in the database.
Note: The above workflow is sequential and cumulative.

The sensor data point timing values can be shortened by changing variables in the CLC.

Important: These changes will increase network traffic as polling will be done more frequently.

To modify metrics defaults:

  1. Modify the default polling interval CLC variable to a number less than 5.
    This is how often the CLC sends a request to the CC for sensor data. Default value is 5 minutes.
  2. Modify the history size CLC variable to a number less than 5.
    This is how many data value samples are sent in each sensor data request. The default value is 5. The frequency requests is either 1 minute (if the cloud.monitor.default_poll_interval_mins is 1 minute) or half the value of cloud.monitor.default_poll_interval_mins if that value is greater).
So by default, with a cloud.monitor.default_poll_interval_mins of 5 minutes and cloud.monitor.history_size size of 5, every 5 minutes the CLC asks for the last 5 data points from the CC, which should be timed for every 2.5 minutes (e.g., 2.5 minutes ago, 5 minutes ago, 7.5 minutes ago, and 10 minutes ago).
Note: These values may be skewed a bit based on the time the CC uses.

For more information, see Eucalyptus Configuration Variables.