Webinar Q&A Impetus webcast ‘Performance Testing of Large-scale Systems’ available at http://lf1.me/UL/

1. Webinar: Performance Testing of Large-scale Systems
September 7, 2012
Question and Answer Session
Q- Can you explain Black-Dye Testing a bit in detail?
A- Black dye test is a term coined by the Impetus’ performance testing team.
This test requires a business scenario to be executed with one single user – for
one single iteration, and the impact of this execution is measured. In this test,
each of the application, web, DB server logs and table entries is analyzed. We
also monitor the various queues where this information flows from. Thereby, we
get a thorough understanding of the penetration of the requests for that
particular workflow. This helps design the performance test scenario.
The name black dye is used because of its analogy with the deep dye test that is
used for identifying the cracks in surfaces.
Q- What are the Cloud-based tools available to assist with performance testing
of Large scale systems?
A- There are numerous load testing tools that can be used on clouds. Infact, any
load testing tool can be deployed on the cloud since its similar to deploy on a
desktop computer. However, very few tools provide a hybrid architecture that
can be used both on cloud as well as from the stand-alone system. One of such
tools is Sandstorm.
Q- What protocols does SandStorm supports?
A- Http, Https, Web Services, POP3, SMTP, DNS, SIP, WAP, Applets, and Java
serialized objects, Flex and Ajax based applications, SNMP, JMX, OMA-IMPS, etc.
Especially for mobile applications, we can also customize the tool for supporting
the custom protocols.
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2. Q- Can SandStom can be used for SOA testing?
A- Yes!
Q- When recording scenario based scripts to use as payloads in the load runner,
does the Impetus tool automatically parameterize like values between multiple
services to create E2E scenarios?
A- Yes, it does. The auto correlation feature helps achieve this.
Q- How do you correlate the various logs, performance counters, and other
instrumentation with the results out of Sandstorm?
A- Sandstorm Analyzer feature helps achieve this. It can also help in super
imposing different graphs to generate the results.
Q- Does Sandstorm do the correlation automatically?
A- Yes
Q- Does Sandstorm offers any perfmon counters?
A- It offers all the counters supported by Perfmon. In addition, it supports various
Linux counters. On the application server, SS supports all popular app, web and
DB servers, provides network statistics, etc.
Q- If cloud is used, what will happen to the countries who dont have high speed
internet? Won’t that pose a problem?
A- It may not be affected by the internet speed. We invite further details
pertaining to your problems so that we can work out a better solution.
Q- You mentioned about Jmeter. Did you use it for Actual Performance test or
to create the test environment?
A- We used JMeter for both.
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3. Q- When testing on a cloud, do we need to consider any networking issues that
might affect our testing?
A- Yes! Infact, we recommend using cloud to simulate the actual user experience
when accessing the application. The cloud can be used to simulate geographies,
control the bandwidth, control the server deployment, etc.
Q- Can sandstorm be used for API testing, WebUI Performance testing?
A- Yes, it can be used for both of these types of testing.
Q- Taking backup of DB table will create many problems because of large data.
Is this the correct way to test performance?
A- For very large data bases, we do not recommend taking a backup. Though, we
do recommend taking a restore point on the database before any performance
test. Once the test gets over, you can go back to the restore point to nullify the
changes done to the DB as part of the performance test.
Q- Can we record the scripts using cloud version of sandstorm?
A- We can!
Q- How do you monitor network latency with Sandstrom?
A- We use the Jamon APIs to measure these statistics.
Write to us at inquiry@impetus.com for more information
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