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<< Number of Virtual Testers Supported Under Normal Conditions | How Different System Configurations Affect Performance >>

How a System Performs Under Stress Conditions

Examples of Performance Tests
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The following table summarizes a sample test that represents overlapping shifts:
How a System Performs Under Stress Conditions
Stress testing can be understood as a relentless attempt to cause a breakdown in the
server. Use a stress test when you suspect the server has some weak areas, which may
break down completely or diminish responsiveness when an operation is performed
many times or over a long period.
Because stress tests involve multiple simultaneous operations (such as sending
hundreds of queries to the server at the same moment), virtual testers provide the
most practical and effective means of performing this type of stress test. Running test
scripts continuously helps you understand the long-term effects of running the
application under stressful conditions.
In a simple stress test, you could create a test where virtual testers perform the same
operation continuously and repeatedly for hours on end. Your test might involve:
s
Inserting thousands of records into a database.
s
Sending thousands of query requests to a database.
Test Scripts
Suite
Reports
A test script to initialize
the database.
A test script to log virtual
testers in.
A test script for each
virtual tester task:
s
adding records
s
deleting records
s
querying the database
s
running payroll reports
A fixed user group with one
virtual tester. This virtual
tester logs in, initializes the
database, and sets an event
indicating that the database
is initialized.
A fixed user group with 100
virtual testers. Each virtual
tester logs in and waits until
the event is set. Each virtual
tester then executes many
iterations of the scenario.
A fixed user group with 200
virtual testers that delays for
2 hours. Each virtual tester
then logs in, checks that the
event is set, and executes
many iterations of the
scenario.
One scenario that contains:
s
a selector to randomly
select a test script
s
a test script for each
virtual tester task
A test log to show whether
all virtual testers in the
suite successfully ran to
completion.
A Command Status report
to show whether the
server completed its
requests successfully.
Two Performance reports:
s
One report on the time
period from the start of
the run until 2 hours
have passed.
s
One report on the time
period from 2 hours
until the end of the run.
A Compare Performance
report comparing the
output of both
Performance reports.