Part II: ProcessesChapter 4.1 Introduction to Process ManagementA process is a program in execution. (프로세스의 정의. 정확하게 따지자면, 프로그램과는 구분된다.)A process has an address space containing a mapping of its program’s object code and global variables. It also has a set of kernel resources that it can name and on which it can operate using system calls. These resources include its credentials, signal state, a..

3.7 Resource ServicesAll systems have limits imposed by their hardware architecture and configuration to ensure reasonable operation and to keep users from accidentally (or maliciously) creating resource shortages. (오오.. 모든 시스템은 한계를 가진다 by 안정성)At a minimum, the hardware limits must be imposed on processes that run on the system. It is usually desirable to limit processes further, below these har..

3.4 Clock InterruptsThe system is driven by a clock that interrupts at regular intervals. Each interrupt is referred to as a tick. On the PC, the clock ticks 1000 times per second. At each tick, the system updates the current time of day as well as user-process and system timers.  Handling 1000 interrupts per second can be time consuming. To reduce the interrupt load, the kernel computes the num..

3.3 Traps and InterruptsTraps, like system calls, occur synchronously for a process. Traps normally occur because of unintentional errors, such as division by zero or indirection through an invalid pointer. The process becomes aware of the problem either by catching a signal or by being terminated. Traps can also occur because of a page fault, in which case the system makes the page available an..

CFS Completely Fair Process Scheduling in Linux