Implementation Guide › Performance Tuning › Data Tier Performance › User Store Capacity Planning › Estimate the Peak User Directory Search Rate › Case: Estimate the Peak User Directory Search Rate

Case: Estimate the Peak User Directory Search Rate

A company has determined the application results in a total of 888,000 operations per day. These operations result in approximately 2,051,520 user directory searches. Using metrics gathered during a capacity planning exercise, the company has determined that during the single busiest hour, approximately 278,000 operations, or 31 percent of the total operations, occurred.

The company uses the following formula to estimate the peak user store search rate.

(total_user_directory_requests * percentage_of_requests) / number_of_hours / 3600 = peak_authentication_request_rate

• total_authentication_requests

  Represents the total number of requests the Policy Server sends to the user store.

• percentage_of_requests

  Represents the percentage of operations that occur when the system is operating at peak levels.

• number_of_hours

  Represents the number of hours in which the system operates at peak levels.

• peak_user_directory_request_rate

  Represents the number of requests, per second, that the Policy Server makes to the user store to maintain the peak authentication rate.

Result: (2,051,520 * 0.31) / 1 / 3600 = 176.6 requests per second.

The Policy Server makes 176.6 requests, per second, to the user directory when servicing authentication and authorization requests during peak levels of operation.