The main aim to design a processor to increase the clock speeds of processor whether it is RISC or SISC processor.In the view of these facts,dual-core processors is introduced in 2005.
A Dual- core processor is exactly what it sounds like. It is two processor cores integrated on one physical chip. Dual-core refers to a CPU that includes two complete execution cores per physical processor. It combines two processors and their caches and cache controllers onto a single integrated circuit (silicon chip).
Dual-core processors are developed for multitasking environments because there are two complete execution cores instead of one.Each of the core with an independent interface to the frontside bus. Since each core has its own cache, the operating system has sufficient resources to handle most complex tasks in parallel.
Multi-core is of an expansion to dual-core technology and allows for more than two separate processors.
The benefit of having multiple processors is the system can handle more than one thread. Each processor can handle a separate stream of data. This highly increases the performance of a system that is running concurrent applications such as a server.
All of the major current operating systems have multithreading capability. But you must have application software that support multithreading.Any speed benefits depends on the operating system that being able to separate applications between the processors.
We know that higher the clock cycle,faster the processor.Most of the early dual-core processors are going to be running at lower clock speeds compared to single core processors. The reason behind that a dual-core processor with each running at 1GHz should be equivalent to a single processor running at 2GBz. It doesn’t work in practice when the applications are not written to take advantage of the multiple processors.Until the software is written this way, unthreaded applications will run faster on a single processor than a dual-core CPU.
Advantage of Dual-core Technology
Dual-core processors support two complete execution cores instead of one, each with an independent interface .Since each core has its own cache, the operating system has sufficient resources to handle complex tasks in parallel, which is implementation of multitasking.
Optimization for the dual-core processor requires both the operating system and applications running on the computer to support a this technology .This level of technology is known as thread-level parallelism i.e.multiple threads running simultaneously.
Today ,Windows XP and hundreds of applications already support multithread technology. Now these days,dual-core technology becomes more common in homes and the workplace.