Generating a bill through Chargeback on different dates for the same billing results in different values for Total charge and Usage for CPU and Memory

Products

• VMware Aria Suite

Issue/Introduction

Found that bills generated for the same time period but generated on different dates have different values for Total Charge and Usage for CPU and Memory.  

For example a bill was generated on the 2nd of November 2023 for billing period of 1st Oct, 2023 to 1st Nov, 2023 , the value for Total Charge for Memory for this bill was 39,575.23 and for Total Charge for CPU it was 37,650.19 .  The usage for Usage for Memory was 10,650.79 and the vCPU was 3,532.02.  

A second bill was generated on the 2nd of September for the same billing period of 1st of October to 1st of November, the value for Total Charge for Memory for this bill was 43,235.19 and for Total Charge for CPU it was 37,200.07 .  The usage for Usage for Memory was 11,897.11 and the vCPU was 3,419.16

Environment

Aria Operations 8.12 and later

Cause

The discrepancy for Total Charge and Usage for CPU and Memory on the bills is due to the data retention period for resources and metrics in Aria Ops. Since the bill reflects usage data that may not be fully retained, so it can vary based on when the bill is generated.

In the example described in Issue/Introduction the billing period is older than a year so it is likely that some of the resources(VApps, VMs etc) are deleted from the system and also the metrics and properties are rolled up once it passes the retention period set in Global settings. 

If the retention period for Deleted Objects is set to 840 hours(35 days) in Global settings and an object was deleted over 35 days ago that resource will no longer exist in Aria Ops ,so if the if the bill is generated again for the same billing period as the resource is no longer is available it wont be counted on the bill. 

Similarly if the Time Series Data Retention is 6 months and the Object history is set to 90 days, when the retention period passes, these will be rolled up and the price calculation will vary. Because of which you are seeing the vCPU and memory cost different for the same billing period.

Resolution

Adjust the retention period for Deleted Objects , Time Series Data Retention and Object history in the Global Settings