Access Events

About this task

Historian uses AWS CloudTrail to capture the consumption of data. Using CloudTrail, you can view the amount of tag data that is written to Data Archiver and the tag data that you fetch from Data Archiver.

An event is generated every hour in CloudTrail, containing the total number of data samples (in millions) that are fetched from Data Archiver in that hour.

For example, suppose you plot the trend chart of tag values in the past hour, and 10,45,000 samples are fetched from Data Archiver. In the event, the usageQuantity is set to 1 (indicating 1 million), and the usageDimension is set to Units Queried (indicating that this event is for fetching data from Data Archiver). The remaining 45,000 samples are added to the ones collected in the next hour.

Similarly, an event is generated every hour, containing the total number of samples (in millions) that are sent to Data Archiver.

For example, if you have 1000 tags, each one set to a resolution of 1 second, 36,00,000 data samples are written to Data Archiver per hour. In the event, usageQuantity is set to 3, and usageDimension is set to Units Stored. The remaining 6,00,000 samples are added to the next hour.

Events are also generated when Data Archiver is started or stopped.

Depending on the data samples sent or fetched from Data Archiver, the price of using Proficy Historian for Cloud is calculated. You can then make the payment to continue using Historian. If, however, you have applied a Historian license, you are not required to pay for the consumption.

Procedure

  1. Log in to the AWS console.
  2. Under All Services > Management & Governance, select CloudTrail.
  3. In the left section, select Event history.
  4. Set the Event source to metering-marketplace.amazonaws.com.
    A list of read/write events to Data Archiver appears. If needed, you can filter the events for a specific time duration.
  5. Select the event whose details you want to access.
    The Meter Usage page appears, displaying the event details. In the Event Record section, the usageDimension parameter indicates whether the event is for fetching data or writing data. The usageQuantity parameter contains the number of samples that are fetched or written in that duration.