OS course notes - CS
... Another important thing to notice is that the operating system is a reactive program. It does not get an input, do some processing, and produce an output. Instead, it is constantly waiting for some event to happen. When the event happens, the operating system reacts. This usually involves some admin ...
... Another important thing to notice is that the operating system is a reactive program. It does not get an input, do some processing, and produce an output. Instead, it is constantly waiting for some event to happen. When the event happens, the operating system reacts. This usually involves some admin ...
第二章 进程与调度 (Processes and Scheduling)
... Creation Process: OS builds the data structures that are used to manage the process and allocates address space to the process. Reasons for Process Creation ...
... Creation Process: OS builds the data structures that are used to manage the process and allocates address space to the process. Reasons for Process Creation ...
Chapter 3 Operating-System Structures 2
... CS.217 Operating System By Ajarn..Sutapart Sappajak,METC,MSIT Chapter 3 Operating-System Structures ...
... CS.217 Operating System By Ajarn..Sutapart Sappajak,METC,MSIT Chapter 3 Operating-System Structures ...
Isolating Faulty Device Drivers
... In our research, we explore the limits on software isolation, rather than proposing hardware changes. Unfortunately, older PC hardware has various shortcomings that make it virtually impossible to build a system where drivers run in full isolation. However, now that modern hardware with support for ...
... In our research, we explore the limits on software isolation, rather than proposing hardware changes. Unfortunately, older PC hardware has various shortcomings that make it virtually impossible to build a system where drivers run in full isolation. However, now that modern hardware with support for ...
Slides for lecture 3
... ■ Represented by the C structure task_struct pid t pid; /* process identifier */ long state; /* state of the process */ unsigned int time slice /* scheduling information */ struct task struct *parent; /* this process’s parent */ struct list head children; /* this process’s children */ struct files s ...
... ■ Represented by the C structure task_struct pid t pid; /* process identifier */ long state; /* state of the process */ unsigned int time slice /* scheduling information */ struct task struct *parent; /* this process’s parent */ struct list head children; /* this process’s children */ struct files s ...
Threads - 5th Semester Notes
... creating and deleting many threads. – A large number of (unlimited) threads could exhaust system resource such as CPU time and memory. • Solution – To create a number threads at process startup and place them into a pool, where they sit and wait for job. – When a server receives a request, it awaken ...
... creating and deleting many threads. – A large number of (unlimited) threads could exhaust system resource such as CPU time and memory. • Solution – To create a number threads at process startup and place them into a pool, where they sit and wait for job. – When a server receives a request, it awaken ...
Critical Section
... Pi enters CS only if: either flag[j] = false or turn = i 2. Progress requirement is satisfied 3. Bounded-waiting requirement is met ...
... Pi enters CS only if: either flag[j] = false or turn = i 2. Progress requirement is satisfied 3. Bounded-waiting requirement is met ...
slides
... Since a CPU scheduling algorithm only select processes in ready queue for execution, it doe not affect the amount of time during which a process executes or does I/O. Therefore, the cost of an algorithm is the amount of time a process has been waiting in the ready queue. ...
... Since a CPU scheduling algorithm only select processes in ready queue for execution, it doe not affect the amount of time during which a process executes or does I/O. Therefore, the cost of an algorithm is the amount of time a process has been waiting in the ready queue. ...
Computer Architecture and Organization
... Progress – Processes not in their critical section may not prevent other processes from entering their critical section Deadlock freedom – If there are one or more processes that want to enter their critical sections, the decision of which process is allowed to enter may not be postponed indefinitel ...
... Progress – Processes not in their critical section may not prevent other processes from entering their critical section Deadlock freedom – If there are one or more processes that want to enter their critical sections, the decision of which process is allowed to enter may not be postponed indefinitel ...
Module 4: Processes
... The objective of multiprogramming is to have some process running at all times, to maximize CPU utilization. The objective of time sharing is to switch the CPU among processes so frequently that users can interact with each program while it is running. To meet these objectives, the process sch ...
... The objective of multiprogramming is to have some process running at all times, to maximize CPU utilization. The objective of time sharing is to switch the CPU among processes so frequently that users can interact with each program while it is running. To meet these objectives, the process sch ...
P 1
... So if we don’t want short running jobs waiting behind long running jobs, why don’t we let the job with the shortest CPU burst go next ...
... So if we don’t want short running jobs waiting behind long running jobs, why don’t we let the job with the shortest CPU burst go next ...
File Systems_PPT_ch04
... – Provide a hierarchical structure to organize files • A folder (directory) is an organizational structure that contains files and may additionally contain subfolders (subdirectories) under it. • The folder connects names to the files that are stored on the disk, which makes it easy for users and pr ...
... – Provide a hierarchical structure to organize files • A folder (directory) is an organizational structure that contains files and may additionally contain subfolders (subdirectories) under it. • The folder connects names to the files that are stored on the disk, which makes it easy for users and pr ...
Workshop 5 Slide
... Low-level formatting, or physical formatting — Dividing a disk into sectors that the disk controller can read and write. To use a disk to hold files, the operating system still needs to record its own data structures on the disk. – Partition the disk into one or more groups of cylinders. – Logical f ...
... Low-level formatting, or physical formatting — Dividing a disk into sectors that the disk controller can read and write. To use a disk to hold files, the operating system still needs to record its own data structures on the disk. – Partition the disk into one or more groups of cylinders. – Logical f ...
Notes
... System Calls • System calls provide the interface between a running program and the operating system. – For example – open input file, create output file, print message to console, terminate with error or normally – Generally available as routines written in C and C++ – Certain low-level tasks (dir ...
... System Calls • System calls provide the interface between a running program and the operating system. – For example – open input file, create output file, print message to console, terminate with error or normally – Generally available as routines written in C and C++ – Certain low-level tasks (dir ...
Embedded Operating Systems and Linux
... What is an Embedded OS? • An embedded OS is an operating system which runs on any embedded platform. • Embedded platforms are generally required to function without human intervention. • A typical embedded system consists of a single-board microcomputer or SOC with an OS and some software loaded in ...
... What is an Embedded OS? • An embedded OS is an operating system which runs on any embedded platform. • Embedded platforms are generally required to function without human intervention. • A typical embedded system consists of a single-board microcomputer or SOC with an OS and some software loaded in ...
What is GNU/Linux?
... Windows uses letters of the alphabet to represent different devices and different hard disk partitions. Under Windows, you need to know what volume (C:, D:,...) a file resides on to select it, the file's physical location is part of it's name. In Linux all directories are attached to the root direct ...
... Windows uses letters of the alphabet to represent different devices and different hard disk partitions. Under Windows, you need to know what volume (C:, D:,...) a file resides on to select it, the file's physical location is part of it's name. In Linux all directories are attached to the root direct ...
Singularity: Rethinking the Software Stack
... In the Singularity project, we have built a new operating system, a new programming language, and new software verification tools. The Singularity operating system incorporates a new software architecture based on software isolation of processes. Our programming language, Sing# [8], is an extension ...
... In the Singularity project, we have built a new operating system, a new programming language, and new software verification tools. The Singularity operating system incorporates a new software architecture based on software isolation of processes. Our programming language, Sing# [8], is an extension ...
Singularity: Rethinking the Software Stack
... In the Singularity project, we have built a new operating system, a new programming language, and new software verification tools. The Singularity operating system incorporates a new software architecture based on software isolation of processes. Our programming language, Sing# [8], is an extension ...
... In the Singularity project, we have built a new operating system, a new programming language, and new software verification tools. The Singularity operating system incorporates a new software architecture based on software isolation of processes. Our programming language, Sing# [8], is an extension ...
Threads and Events
... A thread of execution is the smallest unit of computation that can be scheduled to run by the operating system (OS) or virtual machine (VM). It is responsible for carrying out some part of a computation, possibly an entire program, or possibly only some small part of a program. Every program, even t ...
... A thread of execution is the smallest unit of computation that can be scheduled to run by the operating system (OS) or virtual machine (VM). It is responsible for carrying out some part of a computation, possibly an entire program, or possibly only some small part of a program. Every program, even t ...
Lecture 04 Operating System
... Both M:M and Two-level models require communication to maintain the appropriate number of kernel threads allocated to the application ...
... Both M:M and Two-level models require communication to maintain the appropriate number of kernel threads allocated to the application ...