Understanding Threading

Abstract

Using multiple threads in a process is a common way of providing greater application responsiveness. On multiprocessor systems, extra threads (up to the number of processors) can increase performance by ensuring that all the processors are contributing simultaneously to the processing being carried out by the application. On single-processor systems, extra threads will not improve performance. Too many threads on any system can decrease performance (because of all the time the processor(s) spends thread swapping), but multithreading will improve responsiveness because the application can quickly swap from background processing to managing the user interface when the user does something. Using multiple threads also means that an application can carry on working while it’s waiting for outside events, such as waiting for data to be returned from a Hypertext Transfer Protocol (HTTP) network request.