Analysis of information sources in references of the Wikipedia article "Operating system" in English language version.
Last modified:
Like the trap, the interrupt stops the running program and transfers control to an interrupt handler, which performs some appropriate action. When finished, the interrupt handler returns control to the interrupted program.
The concept of an interrupt is something that has expanded in scope over the years. The 80x86 family has only added to the confusion surrounding interrupts by introducing the int (software interrupt) instruction. Indeed, different manufacturers have used terms like exceptions, faults, aborts, traps and interrupts to describe the phenomena this chapter discusses. Unfortunately there is no clear consensus as to the exact meaning of these terms. Different authors adopt different terms to their own use.
Synchronous implementation of system calls negatively impacts the performance of system intensive workloads, both in terms of the direct costs of mode switching and, more interestingly, in terms of the indirect pollution of important processor structures which affects both user-mode and kernel-mode performance. A motivating example that quantifies the impact of system call pollution on application performance can be seen in Figure 1. It depicts the user-mode instructions per cycles (kernel cycles and instructions are ignored) of one of the SPEC CPU 2006 benchmarks (Xalan) immediately before and after a pwrite system call. There is a significant drop in instructions per cycle (IPC) due to the system call, and it takes up to 14,000 cycles of execution before the IPC of this application returns to its previous level. As we will show, this performance degradation is mainly due to interference caused by the kernel on key processor structures.The concept of an interrupt is something that has expanded in scope over the years. The 80x86 family has only added to the confusion surrounding interrupts by introducing the int (software interrupt) instruction. Indeed, different manufacturers have used terms like exceptions, faults, aborts, traps and interrupts to describe the phenomena this chapter discusses. Unfortunately there is no clear consensus as to the exact meaning of these terms. Different authors adopt different terms to their own use.