Added "Performance" (#30557)

guide/english/computer-hardware/cpu/index.md

@@ -26,6 +26,13 @@ There are two primary manufacturers of computer microprocessors. Intel and Advan
 ### Manufacturers of mobile microprocessors
 The improvements in microprocessor technology have also led to signficant technology advances in CPUs designed specifically for the mobile space. Processors based on designs from ARM, Qualcomm, and others have resulted in new mobile devices with capabilities that are unheard of in past generations. These modern mobile CPUs power popular consumer devices from the latest iteration of Apple iPhones and Android based Phones to IOT(Internet of Things), devices like Amazon Echo and Google Home, with capabilities such as HD Video recording/video conferencing, stereo audio, 3D gaming, and applications that are dependent on mobile CPU performance. This is one of the factors contributing to the growth and adoption of mobile devices which in turn has generated demand and provided opportunity for the creation of new applications with greater capabilities.
 
+### Performance
+The performance or speed of a processor depends on, among many other factors, the clock rate (generally given in multiples of hertz) and the instructions per clock (IPC), which together are the factors for the instructions per second (IPS) that the CPU can perform. Many reported IPS values have represented "peak" execution rates on artificial instruction sequences with few branches, whereas realistic workloads consist of a mix of instructions and applications, some of which take longer to execute than others. The performance of the memory hierarchy also greatly affects processor performance, an issue barely considered in MIPS calculations. Because of these problems, various standardized tests, often called "benchmarks" for this purpose such as SPECint have been developed to attempt to measure the real effective performance in commonly used applications.
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+Processing performance of computers is increased by using multi-core processors, which essentially is plugging two or more individual processors (called cores in this sense) into one integrated circuit.Ideally, a dual core processor would be nearly twice as powerful as a single core processor. In practice, the performance gain is far smaller, only about 50%, due to imperfect software algorithms and implementation. Increasing the number of cores in a processor (i.e. dual-core, quad-core, etc.) increases the workload that can be handled. This means that the processor can now handle numerous asynchronous events, interrupts, etc. which can take a toll on the CPU when overwhelmed. These cores can be thought of as different floors in a processing plant, with each floor handling a different task. Sometimes, these cores will handle the same tasks as cores adjacent to them if a single core is not enough to handle the information.
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+Due to specific capabilities of modern CPUs, such as hyper-threading and uncore, which involve sharing of actual CPU resources while aiming at increased utilization, monitoring performance levels and hardware use gradually became a more complex task. As a response, some CPUs implement additional hardware logic that monitors actual use of various parts of a CPU and provides various counters accessible to software; an example is Intel's Performance Counter Monitor technology.
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 ### Types of Computer CPUs
 The computer CPU is a vital component that handles all the instructions and calculations that are sent to it from other computer's components and peripherals. The speed at which software programs operate is also very dependent upon how powerful the CPU is, so it is important to have the right type for what you expect it to handle. The two leading CPU manufacturers are Intel and AMD, each with their own types of CPUs