What is Soak Testing and Why and When to Perform It

Soak Testing is a non-functional testing within which, the System Underneath Load (SUL) is tested & verified so it will stand up to a large volume of the load for an extended amount of time.

Soak Testing is nothing, however, a kind of a performance check

It is testing at a system level, to seek out whether or not the system can rise to a really high volume of usage and to visualize what would happen outside its design expectations.

Why do Soak Testing?

A system might behave ordinarily when used for two hours, however, once a similar system is employed continuously for ten hours or over that then it might fail or behave abnormally or it may crash. To predict such failure Soak Testing is performed.

When to do Soak Testing?

Soak Testing should be performed in the following scenarios: -

1. Before the build is deployed to the consumer i.e. before the release of any application on a particular platform, it must undergo an imminent series of load tests at high or equivalent traffic levels. Afterward, soak testing is performed. It helps us to see a way to run any specific application for an extended period. If problems like memory leaks/memory corruption are found throughout the period i.e. once it's on Soak, then it should be now reported.
2. The best time to perform soak testing is over the weekends as an application need to be in a running state for as long as over a day or night. It entirely depends on the restrictions of the testing scenario. Soak tests are one of the most important compliance needs, that has to be strictly followed by every company.

Characteristics of Soak Testing

A standard Soak Testing technique should have the following characteristics: -

• The period of most Soak test is usually determined by the time available.
• Any application should run with no interruption if it needs an extended period of time.
• It should cover all the situations that are specified by the stakeholders.
• Mostly every system contains a regular maintenance window period of time and therefore the time between such window periods is a key driver for deciding the scope of a Soak test.

Common issues observed during Soak Testing

• Memory allocation (memory leaks that may eventually lead to a memory crisis or rounding errors that manifest only over time).
• Database resource usage (Failure to shut database cursors below some conditions which might eventually lead to the whole system stalling).
• It can even result in performance degradation, i.e. to confirm that the response time when an extended period of sustained activity is as good as it was at the start of the test.
• Failure to shut connections between tiers of a multi-tiered system below some circumstances that might stall some or all modules of the system.
• The gradual degradation of a reaction time of some functions as internal data-structures become less economical throughout an extended test.