Performance Testing - Non Functional testing requirements

Before starting the Performance testing, performance test engineer should collect non-functional requirement and below is comprehensive list of performance Testing Requirements.

•  Total user base: How many users will have access to this application? 
• Customer will provide answer, how many users are having an access to the application.
• If the application is existing one, Customer will get the data from previous years to understand how many users are using the application. There are third party tools like Web trends to analyze the traffic of existing used application
• If the application is new and not yet in live, Business analyst and Application owners will be able to provide total user base.
• Concurrent User Load: What is the number of total users who will access the application together at any given point in time?
• According to industry standard, it is 10% of total users will be the concurrent load but this formula will not applicable for all the domains.
• Third party tools like web trends will be useful
• Business Processes ( Performance Scenarios):  
• What are the business processes (Workflows) to be performance tested with concurrent users? Objective here is to find few business processes which can cover up to 80% of the application code"
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• Load Distribution :What is the user/Load distribution on each business processes  listed 
• What is the time duration taken for each business process to complete end to end (Workflow)? 
• How often are the users doing each business process (Workflow) in an hour, a day, etc? to get this data for existing application
• Service Level Agreement (Performance - Service Level Agreement):
• What are the acceptable response times for each transaction (page) in all the business flows that needs to be performance tested? Mention SLA for against each of the transaction (page) identified
• 1. All pages within the portal shall load in 3 seconds or less.
• 2. Report should load in 5 sec
• 3. Yearly Report should load in 20 
• 4. SecgetAccountHistory API’s roundtrip response time should be < 250 msec