Tool to calculate 90th percentile for common transactions on a visual studio Load test run


Requirement
As a performance tester, I need to calculate 90th percentile for common transactions, from the Transaction summary of Load Test Runs

Problem Statement
In the visual studio Test transaction summary report, we have scenarios where in same transaction reported multiple times with
different response times(due to load and application behavior).
Example: Login transaction which is used as first transaction in every scenario, can report different response times at different scenarios.
In such case we usually calculate 90th percentile or AVG of common login transactions and report to developers or customer.
This will ensure consistency and provide accurate results.

Problem Solution:
Below is the generic utility, a Sql stored procedure that will automatically calculate 90th percentile for all common
transactions, on various response times(Avg/90thpercentile)

Steps to Execute the Store procedure
1. Connect to LoadTest results database. Create & Execute below Store Procedure
2. Execute below TSQL to create Stored Procedure.

Create Procedure Calc90thPercentileForCommonTransactions @loadtestid int
As
Begin

---- Get visual studio test results to Temptable
Select * into #TempTable
from
(select distinct LTC.TestCaseName,LTTSD.LoadTestRunId, WLTT.TransactionName, LTTSD.Percentile90,
PERCENTILE_CONT ( 0.9 ) WITHIN GROUP ( ORDER BY LTTSD.Percentile90 )
OVER ( partition by WLTT.TransactionName ) as 'CalculatedPercentile90th'
from LoadTestTransactionSummaryData LTTSD
Join WebLoadTestTransaction WLTT on LTTSD.TransactionId = WLTT.TransactionId , LoadTestCase LTC
where LTTSD.LoadTestRunId = @loadtestid
and LTTSD.LoadTestRunId = WLTT.LoadTestRunId
and LTC.TestCaseId = WLTT.TestCaseId and LTTSD.TransactionId = WLTT.TransactionId
and LTC.LoadTestRunId = @loadtestid) as result;

---- Calculate 90th percentile for commonTrasactions
WITH DUP
AS (
SELECT TransactionName
FROM #TempTable
GROUP BY TransactionName
HAVING COUNT(1) > 1)

SELECT t.TestCaseName,t.TransactionName, t.Percentile90 as '90thPercentileFromTestResult',t.CalculatedPercentile90th as '90thPercentileForCommonTransaction',
CASE
WHEN DUP.TransactionName IS NOT NULL
THEN 'Yes'
ELSE 'No'
END AS IsCommonTransaction,
CASE
WHEN DUP.TransactionName IS NOT NULL
THEN CalculatedPercentile90th
ELSE Percentile90
END AS Consolidated90thPercentileToReport
FROM #TempTable T
LEFT JOIN DUP ON T.TransactionName = DUP.TransactionName;

End

3. Stored procedure execution

Exec Calc90thPercentileForCommonTransactions @loadtestid
where loadtestid is the runid of the test.
Example:  Exec Calc90thPercentileForCommonTransactions 1555

4. Below is the result of store procedure
TestCaseName: Name of the TestCase
TransactionName: Name of the Transaction
90thPercentileFromTestResult: 90thPercentile Response from Transaction summary of the Test(Additional Info for debugging purpose)
90thPercentileForCommonTransaction: Calculated 90thPercentile of all Common Transactions on the Response time. (Additional Info for debugging purpose)
IsCommonTransaction: 'Yes' in case if it is common transaction(Present more than once), 'No' in case if it is not a common Transaction(Unique)(Additional Info for debugging purpose)
Consolidate90thPercentileToReport: Final Response time to developers or customer which has 90thpercentile calculated value for all Common Transactions(Present more than once)

Comments (0)

Skip to main content