Solution

To change run settings

1.Open a load test.
2.Expand the Run Settings folder.
3.Choose a Run Settings node.
4.On the View menu, choose Properties Window.The Properties Window is displayed and the properties for the selected run setting are displayed.
5.Use the Properties Window to change the run settings. For example, change the run duration to 00:05:00 to run your test for five minutes.
6.When you are finished changing properties, save your load test. On the File menu, choose Save.

Reference: http://msdn.microsoft.com/en-us/library/ff406976.aspx

Exception

Results from agent 'Test Agent' were not received in time to be included in the overall results for a sampling interval. To avoid this error, increase the sample rate, or decrease the load on this agent

Explanation

Sample Rate property for the load test run setting based on the length of your load test.

Solution

To specify performance counter sampling rate in a run setting

1.Open a load test.The Load Test Editor appears. The load test tree is displayed.
2.In the load test tree, in the Run Settings folder, choose the run setting that you want to specify the sample rate for.
3.On the View menu, select Properties Window.The load run setting's categories and properties are displayed in the Properties window.
4.In the Sample Rate property, enter a time value that indicates the frequency at which the load test will collect performance counter data.
5.After you have finished changing the property, choose Save on the File menu. You can then run your load test using the new Sample Rate value.

Load Test Duration - Recommended Sample Rate
< 1 Hour - 5 seconds
1 - 8 Hours - 15 seconds
8 - 24 Hours - 30 seconds
> 24 Hours - 60 seconds

Reference - http://msdn.microsoft.com/en-us/library/ff423846.aspx

Explanation

When a load test is executed from the local machine the assemblies required to run the test are copied to the controller. The files are copied to a directory on the controller in the following location Drive:\Users\[USER]\AppData\Local\VSEQT\QTController.The Test results are copied to a directory on the controller in the following location Drive:\Users\<Account>\AppData\Local\VSEQT\QTController\TestRunStorage.
Each deployment and TestRunStorage will have a further directory named with a unique GUID where the files are copied.

For example

Deployment folder location: C:\Users\[USER ACCOUNT]\AppData\Local\VSEQT\QTController\[GUID]
TestRunStorage folder location : C:\Users\[USER ACCOUNT]\AppData\Local\VSEQT\QTController\TestRunStorage\[GUID]

Workaround

Delete the folders under C:\Users\[USER ACCOUNT]\AppData\Local\VSEQT\QTController\. or a scheduled task to delete the folders periodically

Solution

Problem

The load test rig database was configured on SQL Server 2008 express edition which can hold maximum database size of 4 gb

Workaround

Note: Always test the blog script on your test environment before executing on production environment

This problem can be overcame by removing historical results

-- Start Script

-- This script deletes all load test run older than two weeks
-- To change the timeframe, change the number of days from 14 to the desired number
 
USE LoadTest
DECLARE @LoadTestRunId int
DECLARE OldLoadTestsCursor CURSOR FOR
    SELECT LoadTestRunId FROM LoadTestRun WHERE datediff(dd, StartTime, getdate()) > 14
 
OPEN OldLoadTestsCursor
FETCH NEXT FROM OldLoadTestsCursor INTO @LoadTestRunId
 
WHILE @@FETCH_STATUS = 0
BEGIN
    EXEC Prc_DeleteLoadTestRun @LoadTestRunId
    FETCH NEXT FROM OldLoadTestsCursor INTO @LoadTestRunId
END
 
CLOSE OldLoadTestsCursor
DEALLOCATE OldLoadTestsCursor

-- End Script

Script Reference :  http://blogs.msdn.com/b/billbar/archive/2006/02/09/528900.aspx

Solution

Configure the rig to other editions of SQL server.