Saturday, 17 March 2012

Transaction points

1. What is Transaction Response Time?
Transaction Response Time represents the time taken for the application to complete a defined transaction or business process.
2. Why is important to measure Transaction Response Time?
The objective of a performance test is to ensure that the application is working perfectly under load. However, the definition of “perfectly” under load may vary with different systems.
By defining an initial acceptable response time, we can benchmark the application if it is performing as anticipated.
The importance of Transaction Response Time is that it gives the project team/ application team an idea of how the application is performing in the measurement of time. With this information, they can relate to the users/customers on the expected time when processing request or understanding how their application performed.
3. What does Transaction Response Time encompass?
The Transaction Response Time encompasses the time taken for the request made to the web server, there after being process by the Web Server and sent to the Application Server, which in most instances will make a request to the Database Server. All this will then be repeated again backward from the Database Server, Application Server, Web Server and back to the user. Take note that the time taken for the request or data in the network transmission is also factored in.
To simplify, the Transaction Response Time comprises of the following:
1. Processing time on Web Server
2. Processing time on Application Server
3. Processing time on Database Server
4. Network latency between the servers, and the client.
4. What are the functions used to calculate the Transaction Response Time?
lr_start_transaction(“Variable Name”);
lr_end_transaction(“Variable Name”, LR_AUTO);

lr_end_transaction(“Variable Name”, LR_PASS);
lr_end_transaction(“Variable Name”, LR_FAIL);
lr_start_transaction(“Variable Name”);
step1 (http request)
lr_end_transaction(“Variable Name”, LR_AUTO);

5. How do you add transactions in loadrunner vugen? 

Transactions in VuGen can be added four ways:

1) During recording, click on add start transactions and end transactions
2) After recording from Enhancements section of Tasks (By inserting functions manually after recording the script).
3) After recording from Tree view
4) After recording from script view
Key points about transaction in loadrunner

  • Transactions points help measure performance of your system under test.
  • You can have any number of transactions in your script
  • A transaction can have sub-transactions