Operating System Essay Example | Topics and Well Written Essays - 1750 words

Operating System - Essay Example (e.g. for a system call). This mechanism is used to prevent programming mistakes with system resources. It also shares common system resources in an appropriate manner under OS control. It prevents accessibility to protected memory segments. It also identifies instructions that can cause error conditions and inconsistent system state. Memory location of interrupt handler that signifies interrupts and also will save them in a queue if multiple interrupts are in processing, is called interrupt vector. The interrupt vector is a matrix of pointers to specific interrupt-handling routines. A hardware part that is called the device controller along with any device makes up the computer system. The device controllers basically acts as an interface between the device and the OS of that computer. Device controllers is also responsible of transferring data from other devices that controls it and the local buffers. To store and execute necessary commands in device controller, registers and buffers are integrated in the device controller. To provide interface between a device controller and OS, there is a device driver in OS that presents a steady interface into the device. First the device driver is introduced in to the OS to which the device is to be connected and then User and the system can exchange data with help of device through the device itself. In multiprocessor, two copies of the same data may reside in the local cache of each CPU. If one of the CPU changes the data, the Caches of the other cache coherency includes. Storing the data in multiple caches signifies one of the best ways of storing data. In this kind of shared memory, there is different cache memory for each of the processors. It is possible that many copies of one direction operand would exist on multiple caches that would exist on different processors. If one copy is changed, all the copies that are present on the other