Software Performance testing is type of testing perform to determine the performance of system to major the measure, validate or verify quality attributes of the system like responsiveness, Speed, Scalability, Stability under variety of load conditions. The system is tested under a mixture of load conditions and check the time required responding by the system under varying workloads. Software performance testing involves the testing of application under test to ensure that application is working as expected under variety of load conditions. The goal of performance testing is not only find the bugs in the system but also eliminate the performance bottlenecks from the system.
Common Performance Problems:
In the software testing of an application Speed is one of the important attribute. User will not happy to work with slow system. The performance testing uncovers the performance bottlenecks & defects to maintain interest and attention of user. Here is the list of most commonly performance problems observed in software system:

Poor response time
Long Load time
Poor scalability
Software configuration issues (for the Web server, load balancers, databases etc.)
Disk usage
Operating System limitations
Poor network configuration
Memory utilization
CPU utilization
Insufficient hardware resources

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