No Slide Title
... A request for kernel-mode execution can occur in two ways: A running program may request an operating system service, either explicitly via a system call, or implicitly, for example, when a page fault occurs. A device driver may deliver a hardware interrupt that causes the CPU to start executi ...
... A request for kernel-mode execution can occur in two ways: A running program may request an operating system service, either explicitly via a system call, or implicitly, for example, when a page fault occurs. A device driver may deliver a hardware interrupt that causes the CPU to start executi ...
Computer Systems II Gordon College
... An Operating System must be able to: • provide functionality to apps • provide abstraction of hardware to users and apps • provide the sharing of resources to processes • provide security and protection • be as transparent as possible • be as light as possible ...
... An Operating System must be able to: • provide functionality to apps • provide abstraction of hardware to users and apps • provide the sharing of resources to processes • provide security and protection • be as transparent as possible • be as light as possible ...
Lecture 1 - Department of Computer Science
... – Manages each process within the jobs – Monitors whether CPU is executing a process or waiting for a ‘read’ or ‘write’ command to finish executing – Once the CPU has been allocated, sets up required registers and tables – Keeps track of the status of each process – Reclaims the CPU once the jo ...
... – Manages each process within the jobs – Monitors whether CPU is executing a process or waiting for a ‘read’ or ‘write’ command to finish executing – Once the CPU has been allocated, sets up required registers and tables – Keeps track of the status of each process – Reclaims the CPU once the jo ...
Processes - UCSB Computer Science
... Producer writes to one end (the write-end of the pipe) Consumer reads from the other end (the read-end of the pipe) Ordinary pipes are therefore unidirectional Require parent-child relationship between communicating processes ...
... Producer writes to one end (the write-end of the pipe) Consumer reads from the other end (the read-end of the pipe) Ordinary pipes are therefore unidirectional Require parent-child relationship between communicating processes ...
The Java Virtual Shell and Kernel
... 1. To develop a graphical user interface of the user to enter the commands and an area where the user will get the output of the command issued. 2. To develop a shell program this will receive the command issued by the users to the user interface and validate them against the set of the commands and ...
... 1. To develop a graphical user interface of the user to enter the commands and an area where the user will get the output of the command issued. 2. To develop a shell program this will receive the command issued by the users to the user interface and validate them against the set of the commands and ...
6. Process Synchronization
... instance, a shared file), we must provide an environment to allow concurrent access to these types of resources. Computation speedup: If we want a particular task to run faster, we must break it into subtasks, each of which will be executing in parallel with the others. Such a speedup can be achieve ...
... instance, a shared file), we must provide an environment to allow concurrent access to these types of resources. Computation speedup: If we want a particular task to run faster, we must break it into subtasks, each of which will be executing in parallel with the others. Such a speedup can be achieve ...
Flowcharting Concepts
... one cup of flour.” A rectangle can also indicate an entire subprocess within a larger process, such as “Make cake.” In most flowcharts, the rectangle symbol is used most frequently. A line with an arrow indicates the sequence of steps and the direction of the flow of work. This represents a mon ...
... one cup of flour.” A rectangle can also indicate an entire subprocess within a larger process, such as “Make cake.” In most flowcharts, the rectangle symbol is used most frequently. A line with an arrow indicates the sequence of steps and the direction of the flow of work. This represents a mon ...
Processes
... modifiable part of the user space. May include program data, a heap area, and programs that may be modified. ...
... modifiable part of the user space. May include program data, a heap area, and programs that may be modified. ...
Race Conditions
... • Using C we will simply pass in the semaphore structure to related functions. • After initialization, the semaphore only works with two operations: acquire (also called wait) and release (also called signal). • Semaphores can be used to count or in a binary fashion (to provide only mutual exclusion ...
... • Using C we will simply pass in the semaphore structure to related functions. • After initialization, the semaphore only works with two operations: acquire (also called wait) and release (also called signal). • Semaphores can be used to count or in a binary fashion (to provide only mutual exclusion ...
Ch-4_3431
... with one thread and doing input with another Resource Sharing: Automatic sharing of code and (some) data for an application Economy: Easier to make and less memory intensive than a process Scalability(?): Allows a process to use multiple ...
... with one thread and doing input with another Resource Sharing: Automatic sharing of code and (some) data for an application Economy: Easier to make and less memory intensive than a process Scalability(?): Allows a process to use multiple ...
A User Mode L4 Environment
... L4 Linux-applications have no different behavior than standard Linux applications and can be developed and debugged in the same way. But L4 Linux applications additionally can use the L4 microkernel functions. On the first glance, enough tools and support is available. But despite the continuous eff ...
... L4 Linux-applications have no different behavior than standard Linux applications and can be developed and debugged in the same way. But L4 Linux applications additionally can use the L4 microkernel functions. On the first glance, enough tools and support is available. But despite the continuous eff ...
Questionaire
... 3. What are typical process states and typical transitions between these states. ...
... 3. What are typical process states and typical transitions between these states. ...
Self-Assessment Interactive Topic 1
... Answer: Gradual increase of priority with age of job, to prevent “starvation.” 5.11 What is SRTF (Shortest-Remaining-Time-First) scheduling? Answer: A preemptive scheduling algorithm that gives high priority to a job with least amount of CPU burst left to complete. 5.12 What is round-robin schedulin ...
... Answer: Gradual increase of priority with age of job, to prevent “starvation.” 5.11 What is SRTF (Shortest-Remaining-Time-First) scheduling? Answer: A preemptive scheduling algorithm that gives high priority to a job with least amount of CPU burst left to complete. 5.12 What is round-robin schedulin ...
CS307-slides01
... What is an Operating System? An operating system is a program that manages the computer hardware A program that acts as an intermediary between the computer user and the ...
... What is an Operating System? An operating system is a program that manages the computer hardware A program that acts as an intermediary between the computer user and the ...
Lecture OS - University of Wisconsin
... all stored in the user process’ address space simple management — creating a new thread, switching between threads, and synchronization between threads can all be done without intervention of the kernel fast — thread switching is not much more expensive than a procedure call flexible — CPU sch ...
... all stored in the user process’ address space simple management — creating a new thread, switching between threads, and synchronization between threads can all be done without intervention of the kernel fast — thread switching is not much more expensive than a procedure call flexible — CPU sch ...
... a few. A byte is 8 bits, and on most computers it is the smallest convenient chunk of storage. For example, most computers don’t have an instruction to move a bit but do have one to move a byte. A less common term is word, which is a given computer architecture’s native unit of data. A word is made ...
Kernel designs explained
... individual bags to one another with strings (the IPC). The total weight of the end result will be that of the original beef, plus that of the plastic bags and string. Therefore, while a microkernel may appear simple on a very local level, at a global level it will be much more complex than a similar ...
... individual bags to one another with strings (the IPC). The total weight of the end result will be that of the original beef, plus that of the plastic bags and string. Therefore, while a microkernel may appear simple on a very local level, at a global level it will be much more complex than a similar ...
Chapter 1
... ★A program that determines nature of the interrupt and performs whatever actions are needed (Determines which types of ...
... ★A program that determines nature of the interrupt and performs whatever actions are needed (Determines which types of ...
threads
... Difficulty: in cases where resources have been allocated to a canceled thread or where a thread is canceled while in the midst of updating data it is sharing with other threads ...
... Difficulty: in cases where resources have been allocated to a canceled thread or where a thread is canceled while in the midst of updating data it is sharing with other threads ...
Chapter 3: Processes
... Processes within a system may be independent or cooperating Independent process cannot affect or be affected by the execution of another ...
... Processes within a system may be independent or cooperating Independent process cannot affect or be affected by the execution of another ...
process
... Communicating Between Processes • Shared access to the same memory is dangerous – need to synchronize access ...
... Communicating Between Processes • Shared access to the same memory is dangerous – need to synchronize access ...
slides.02.pdf
... bit: shortest jobs get queued at the head, but running jobs are never preempted. (there’s a problem here – what is it?) However, you will not get an optimum. 2: You have to know the completion time per job ⇒ use estimates based on previous runs, e.g. Tk+1 = a · Tk−1 + (1 − a) · Tk Question: What hap ...
... bit: shortest jobs get queued at the head, but running jobs are never preempted. (there’s a problem here – what is it?) However, you will not get an optimum. 2: You have to know the completion time per job ⇒ use estimates based on previous runs, e.g. Tk+1 = a · Tk−1 + (1 − a) · Tk Question: What hap ...
Computer Architecture and Organization
... simultaneously, OS must ensure that incorrect or malicious program cannot cause other programs to execute incorrectly Provide hardware support (mode bit) to differentiate at least two modes of operations ...
... simultaneously, OS must ensure that incorrect or malicious program cannot cause other programs to execute incorrectly Provide hardware support (mode bit) to differentiate at least two modes of operations ...
Computer Hardware
... Does not load instructions into main memory No user interface except for I/O routines provided with executing program Is idle when waiting for user input No facility to store, retrieve, or manipulate files No ability to control peripheral devices Can run only one program at a time Chapte ...
... Does not load instructions into main memory No user interface except for I/O routines provided with executing program Is idle when waiting for user input No facility to store, retrieve, or manipulate files No ability to control peripheral devices Can run only one program at a time Chapte ...