Load/Volume Test

Load/volume tests study how a program handles large amounts of data, excessive calculations, and excessive processing. These tests do not necessarily have to push or exceed upper functional limits. Load/volume tests can, and usually must, be automated.

Focus of Load/Volume Testing:

* Pushing through large amounts of data with extreme processing demands.
* Requesting many processes simulateously.
* Repeating tasks over a long period of time

Load/volume tests, which involve extreme conditions, are normally run after the execution of feature-level tests, which prove that a program functions correctly under normal conditions.

Difference between Load and Stress testing:

The idea of stress testing is to find the breaking point in order to find bugs that will make that break potentially harmful. Load testing is merely testing at the highest transaction arrival rate in performance testing to see the resource contention, database locks etc..

Web Capacity Testing Load and Stress:

The performance of the load or stress test Web site should be monitored with the following in mind:

* The load test should be able to support all browser
* The load test should be able to support all Web server.
* The tool should be able to simulate up 500 users or playback machines
* The tool should be able to run on WIndows NT, Linux, Solaris, and most Unix variants.
* There should be a way to simulate various users at different connection speeds.
* After the tests are run, you should be able to report the transactions, URL, and number of users who visited the site.
* The test cases should be asssembled in a like fashion to set up test suites.
* There should be a way to test the different server and port addresses.
* There should be a way to account for the user's cookies.


Performance Test:

The primary goal of performance-testing is to develop effective enhancement strategies for maintaining acceptable system performance. Performance testing is a capacity analysis and planning process in which measurement data are used to predict when load levels will exhaust system resources.

The Mock Test:

It is a good idea to set up mock test before you begin your actual test. This is a way to measure the server's stressd performance. As you progress with your stress testing, you can set up a measurement of metrics to determine the efficiency of the test.

After the initial test, you can determine the breaking point for the server. It may be a processor problem or even a memory problem. You need to be able to check your log to determine the average amount of time that it takes your provessor to perform the test. Running graphics or even ASP pages can cause processor problems and a limitation every time you run your stress test.

Memory tends to be a problem with the stress test. This may be due to a memary leak or lack of memory. You need to log and monitor the amount of disk capacity during the stress test. As mentioned earlier, the bandwidth can account for the slow down of the processing of the Web site speed. If the test hanges and there is a large waiting period, your processor usage is too low to handle the a,ount of stress on the system.

Simulate Resources:

It is important to be able to run system in a high-stress format so that you can actually simulate the resources and understand how to handle a specific load. For example, a bank transaction processing system may be designed to process up to 150 transactions per second, whereas an operating system may be designed to handle up to 200 separate terminals. The different tests need to be designed to ensure that the system can process the expected load. This type of testing usually involves planning a series of tests where the load is gradually increased to reflect the expected usage pattern. The stress tests can steadily increase the load on the system beyond the maximum design load until the system fails.

This type of testing has a dual function of testing the system for failure and looking for a combination of events that occur when a load is placed on the server. Stress testing can then determine if overloading the system results in loss of data or user sevice to the customers The use of stress testing is particularly relevant to an ecommerce system with Web database.