2. Operating System Models
... hardware easier to use. They create a virtual machine that differs markedly from the real machine. Indeed, the computer revolution of the last two decades is due, in part, to the success that operating systems have achieved in shielding users from the obscurities of computer hardware. Second, an ope ...
... hardware easier to use. They create a virtual machine that differs markedly from the real machine. Indeed, the computer revolution of the last two decades is due, in part, to the success that operating systems have achieved in shielding users from the obscurities of computer hardware. Second, an ope ...
Processes - UniMAP Portal
... a virtual address space to hold the process image control of some resources (files, I/O devices...), OS prevent interferences between processes with respect to these resources ...
... a virtual address space to hold the process image control of some resources (files, I/O devices...), OS prevent interferences between processes with respect to these resources ...
Process - Tufts Computer Science
... A small glue function (e.g. read()) prepares its arguments in registers Angry Birds or stack, then executes an instruction that “traps” to the kernel. This is known as a “system call”. ...
... A small glue function (e.g. read()) prepares its arguments in registers Angry Birds or stack, then executes an instruction that “traps” to the kernel. This is known as a “system call”. ...
Chapter 3 Process Description and Control
... I/O Tables • Used by the OS to manage the I/O devices and channels of the computer. • The OS needs to know – Whether the I/O device is available or assigned – The status of I/O operation – The location in main memory being used as the source or destination of the I/O transfer ...
... I/O Tables • Used by the OS to manage the I/O devices and channels of the computer. • The OS needs to know – Whether the I/O device is available or assigned – The status of I/O operation – The location in main memory being used as the source or destination of the I/O transfer ...
slides - Simon Fraser University
... Problem: Starvation – low priority processes may never execute Solution? Aging: Increase the priority of a process as it waits in the system ...
... Problem: Starvation – low priority processes may never execute Solution? Aging: Increase the priority of a process as it waits in the system ...
Process Description and Control
... I/O Tables • Used by the OS to manage the I/O devices and channels of the computer. • The OS needs to know – Whether the I/O device is available or assigned – The status of I/O operation – The location in main memory being used as the source or destination of the I/O transfer ...
... I/O Tables • Used by the OS to manage the I/O devices and channels of the computer. • The OS needs to know – Whether the I/O device is available or assigned – The status of I/O operation – The location in main memory being used as the source or destination of the I/O transfer ...
Processes - United International College
... I/O Tables • Used by the OS to manage the I/O devices and channels of the computer. • The OS needs to know – Whether the I/O device is available or assigned – The status of I/O operation – The location in main memory being used as the source or destination of the I/O transfer ...
... I/O Tables • Used by the OS to manage the I/O devices and channels of the computer. • The OS needs to know – Whether the I/O device is available or assigned – The status of I/O operation – The location in main memory being used as the source or destination of the I/O transfer ...
Operating System Layer
... Process location policies may be static or adaptive. Static policies operate without regard to the current state of the system, although they are designed according to the optimizing a system parameter such as the overall process throughput. ...
... Process location policies may be static or adaptive. Static policies operate without regard to the current state of the system, although they are designed according to the optimizing a system parameter such as the overall process throughput. ...
Threads - efreidoc.fr
... represented internally by objects e.g. files are represented by objects, as are user programs when they are running on the computer, hardware resources like printers, communication ports, etc. Motivation behind this is to provide a very modular structure which it is easy to update, extend, etc. ...
... represented internally by objects e.g. files are represented by objects, as are user programs when they are running on the computer, hardware resources like printers, communication ports, etc. Motivation behind this is to provide a very modular structure which it is easy to update, extend, etc. ...
Operating Systems
... Security Services • Security systems must control vulnerabilities that lead to system failures such as incorrect data, erased disks, loss of confidentiality, denial of ...
... Security Services • Security systems must control vulnerabilities that lead to system failures such as incorrect data, erased disks, loss of confidentiality, denial of ...
Chapter 3 Process Description and Control
... The concept of process is fundamental to the structure of modern computer operating systems. Its evolution in analyzing problems of synchronization, deadlock, and scheduling in operating systems has been a major intellectual contribution of computer science. ...
... The concept of process is fundamental to the structure of modern computer operating systems. Its evolution in analyzing problems of synchronization, deadlock, and scheduling in operating systems has been a major intellectual contribution of computer science. ...
Operating Systems (Notes to prepare in 1 night before Exam)
... A mechanism for process communication. A mechanism for deadlock handling. 2. Memory Management:• Keeping track of which parts of memory are currently being used and by whom. • Deciding which processes (or parts thereof) and data to move into and out of memory. • Allocating and deallocating memory sp ...
... A mechanism for process communication. A mechanism for deadlock handling. 2. Memory Management:• Keeping track of which parts of memory are currently being used and by whom. • Deciding which processes (or parts thereof) and data to move into and out of memory. • Allocating and deallocating memory sp ...
Operating System Structure
... Chapter 2: Operating-System Structures Operating System Services User Operating System Interface System Calls Types of System Calls System Programs Operating System Design and Implementation Operating System Structure Operating System Debugging Operating System Generation ...
... Chapter 2: Operating-System Structures Operating System Services User Operating System Interface System Calls Types of System Calls System Programs Operating System Design and Implementation Operating System Structure Operating System Debugging Operating System Generation ...
Operating Systems
... • If we enforce a rule that only one process may enter the function at a time then: • P1 & P2 run on separate processors • P1 enters echo first, – P2 tries to enter but is blocked – P2 suspends • P1 completes execution – P2 resumes and executes echo • This example shows that it is necessary to prote ...
... • If we enforce a rule that only one process may enter the function at a time then: • P1 & P2 run on separate processors • P1 enters echo first, – P2 tries to enter but is blocked – P2 suspends • P1 completes execution – P2 resumes and executes echo • This example shows that it is necessary to prote ...
Module 7: Process Synchronization
... System Model Assures that operations happen as a single logical unit of work, in its ...
... System Model Assures that operations happen as a single logical unit of work, in its ...
Interlude: Process API - Computer Sciences User Pages
... signals subsystem provides a rich infrastructure to deliver external events to processes, including ways to receive and process those signals. There are many command-line tools that are useful as well. For example, using the ps command allows you to see which processes are running; read the man page ...
... signals subsystem provides a rich infrastructure to deliver external events to processes, including ways to receive and process those signals. There are many command-line tools that are useful as well. For example, using the ps command allows you to see which processes are running; read the man page ...
Linux Operating System
... There are a couple of special characters intercepted by the shell, bash. The character “”, an asterix, says “replace this word with all the files that will fit this specification”. So, the command cp data ˜/backup, like the one above, gets changed to cp data-new data 1 data 2 data 5 ˜/backup befor ...
... There are a couple of special characters intercepted by the shell, bash. The character “”, an asterix, says “replace this word with all the files that will fit this specification”. So, the command cp data ˜/backup, like the one above, gets changed to cp data-new data 1 data 2 data 5 ˜/backup befor ...
Migration
... If the home host suffers from a bursty load, it may not make sense to migrate a process -- the home host will be free again, soon. Processes with significant virtual memory or IPC usage or many open files are poor choices for migration. Historical consideration: long running processes are better can ...
... If the home host suffers from a bursty load, it may not make sense to migrate a process -- the home host will be free again, soon. Processes with significant virtual memory or IPC usage or many open files are poor choices for migration. Historical consideration: long running processes are better can ...
Amoeba Vs. Mach OS
... Mach Design Goals Multiprocessor operation: Execute on a shared memory multiprocessor. Both kernel-mode threads and user-mode threads could be executed by any processor. Operating system emulation: To support the binary-level emulation of UNIX and other operating systems. Mach allows for the transp ...
... Mach Design Goals Multiprocessor operation: Execute on a shared memory multiprocessor. Both kernel-mode threads and user-mode threads could be executed by any processor. Operating system emulation: To support the binary-level emulation of UNIX and other operating systems. Mach allows for the transp ...
Implementing File Systems
... Some system uses contiguous allocation for small files and automatically switching to an index allocation if the file grows large ...
... Some system uses contiguous allocation for small files and automatically switching to an index allocation if the file grows large ...
Chapter 1
... I/O devices and the CPU can execute concurrently. Each device controller is in charge of a particular device type. Depending on the device controller, there may be more than one attached device. For example seven or more devices can be attached to a SCSI (small computer system interface) controlle ...
... I/O devices and the CPU can execute concurrently. Each device controller is in charge of a particular device type. Depending on the device controller, there may be more than one attached device. For example seven or more devices can be attached to a SCSI (small computer system interface) controlle ...
Windows Server 2008
... • Some users keep most of their files in the computer’s primary level or root directory (root folder) • Some programs use an automated setup that suggests folders for new programs – Example – creating new subfolders under the Program Files folder ...
... • Some users keep most of their files in the computer’s primary level or root directory (root folder) • Some programs use an automated setup that suggests folders for new programs – Example – creating new subfolders under the Program Files folder ...
OperatingSystems_FA15_13_IO_Systems
... into interrupt vector. 4) Stores the interrupt vector in controller I/O port, allowing CPU to read it via data bus. 5) Sends raised signal to the CPU INTR pin (issues an interrupt). 6) CPU reads interrupt vector and indexes into the IDT, containing ISRs for the interrupt. 7) PIC waits until CPU ackn ...
... into interrupt vector. 4) Stores the interrupt vector in controller I/O port, allowing CPU to read it via data bus. 5) Sends raised signal to the CPU INTR pin (issues an interrupt). 6) CPU reads interrupt vector and indexes into the IDT, containing ISRs for the interrupt. 7) PIC waits until CPU ackn ...
OPERATINGSYSTEMS 2015
... 86. Discuss disk free space management. 87. Discuss directory implementation using: (i) Linear list (ii) Hash table 88. Describe the variable partition scheme with the allocation policies–first fit, best fit and worst fit. Mention a disadvantage of best fit. 89. Explain the different disk space allo ...
... 86. Discuss disk free space management. 87. Discuss directory implementation using: (i) Linear list (ii) Hash table 88. Describe the variable partition scheme with the allocation policies–first fit, best fit and worst fit. Mention a disadvantage of best fit. 89. Explain the different disk space allo ...