Implementation Guide › Performance Tuning › Data Tier Performance › User Store Capacity Planning › How to Estimate a Sustained User Directory Search Rate › Estimate the Sustained User Directory Search Rate › Case: Estimate the Sustained User Directory Search Rate

Case: Estimate the Sustained User Directory Search Rate

The company has determined that:

• The daily authentication load and authorization load for the application result in approximately 888,000 total operations.
• The total operations result in approximately 2,051,520 user directory requests.
• The system is operating at sustained levels for approximately five hours (9:00 AM - 2:00 PM).
• During sustained levels, approximately 84,000 operations occur, per hour.
• Approximately 420,000 (84,000 * 5) operations, or 48 percent (420,000 / 880,000) of the total operations, occur during these hours.

The company uses the following formula to estimate the sustained user store search rate:

(total_user_directory_requests * percentage_of_requests) / number_of_hours / 3600 = sustained_user_directory_search_rate

• total_user_directory_requests

  Represents the daily number of requests the Policy Server makes to the user directory to service authentication and authorization requests.

• percentage_of_requests

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

• number_of_hours

  Represents the number of hours when the system is operating at a sustained rate.

• sustained_user_directory_search_rate

  Represents the number of requests, per second, the Policy Server makes to the user directory to maintain the sustained rate of operation.

Result: (2,051,520 * 0.48) / 5 /3600 = 54.7 user directory requests per second.

The Policy Server makes 54.7 requests, per second, to the user directory when servicing authentication and authorization requests during sustained levels of operation.