Transaction Handling

Handling transactions in LoadRunner

The actual activities of an application by real users are represented by a series of end-user actions called transactions. Multiple requests or a series of actions sent to the server with a fixed frequency (SLA) can be included in a transaction.

     Micro Focus LoadRunner uses transactions to measure server performance. Each transaction counts the number of seconds it takes for the server to respond to a given Vuser request. These requests can be simple processes, such as waiting for a response to a single question, or complex processes, such as submitting multiple questions and creating a report.

There is no limit to the number of transactions or subtransactions a LoadRunner script can have, each with a unique name. Ideally, each user activity is recorded in a separate transaction. To illustrate: login, search, sort, log out, etc. Each transaction has a separate section that is divided into a start and end transaction function. The controller measures the time it takes for a transaction to complete, from when the request is sent to the server until the complete response is received.

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How can transactions be added to a LoadRunner script?

Transactions can be added to the script in two different ways.

1. During recording: A floating toolbar with the “Insert Start Transaction” button is visible when you start recording a script.

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To add a transaction name, click “Add” or “Ctrl+T” on the keyboard and then “Insert Start Transactions”.

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The ‘Insert Final Transaction’ button becomes active when you click ‘OK’.

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To end the transaction, click “Insert End Transaction” or press “Ctrl+Shift+T”. Choose the transaction you want to cancel from a list of transactions started after clicking “Insert Final Transaction”. This option helps to avoid the open transaction error.

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You can also insert subtransactions, or one transaction inside another. Make sure you complete the transaction in the correct order by following the steps.

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2. After burning: Right-click the script at the desired location after burning, then choose “Start Transaction” or hover over “Insert”.

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or choose Layout. Start transaction after inserting in script

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or click ‘Ctrl+T’.

The above step causes VuGen to call lr_start_transaction(“”); in the Vuser script. The name of the transaction can be passed as input to the function, for example, lr_start_transaction(“Start session”). Follow the same procedures and select “Finish transaction” to complete the transaction.

Observation:

• In the ‘lr_start_transaction’ and ‘lr_end_transaction’ functions, the transaction name must match absolutely.
• A transaction name cannot contain the symbols “. (dot), “@ (at the rate), “: (colon), ” > & | (comparison/conditional operators),” or “, (comma). When trying to open the graphs of the cross-scan results, certain characters may cause problems.
• Script replay status is not always updated to Failed after a failed transaction.
• Think time, rendezvous, and flow logic should not be included in a transaction.

The features are described as:

1. lr_start_transaction: first This function starts a certain scripted transaction. The argument is treated as a string of integer return type. If this method is successful, 0 is returned. If the transaction name is not allowed, -1 is returned.
2. lr_end_transaction: The function closes an existing transaction. The transaction name parameter is treated as a string, while the transaction status argument is treated as an integer. If successful, this method returns 0. If there has not been a previous call to lr_start_transaction with a transaction of the same name, or if the transaction name is illegitimate, it returns -1.
   • Success (returns 0) for LR_PASS.
   • Fail (return 1): LR_FAIL
3. LR_AUTO: The status value is determined automatically. This default value is LR_PASS, which indicates a successful transaction (return 2).
   • Canceled (return 3), LR_STOP
     
     Example
   • lr_start_transaction(“01_HomePage”);
   • status = active_site();
   • if (status == 0)
   • lr_end_transaction(“01_HomePage”, LR_PASS);
   • otherwise
   • lr_end_transaction(“01_HomePage”, LR_FAIL);
   • or choose Layout. Start transaction after insert in script