Module 7: Process Synchronization
... Resource types R1, R2, . . ., Rm CPU cycles, memory space, I/O devices Each resource type Ri has Wi instances. Each process utilizes a resource as follows: request use release ...
... Resource types R1, R2, . . ., Rm CPU cycles, memory space, I/O devices Each resource type Ri has Wi instances. Each process utilizes a resource as follows: request use release ...
lecture1
... 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 ...
... 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 ...
Operating System
... Multiprogramming assumes a single processor that is being shared. It increases CPU utilization by organizing jobs so that the CPU always has one to execute. switches occur so frequently that the users may interact with each program while it is running. Time-sharing systems were developed to provide ...
... Multiprogramming assumes a single processor that is being shared. It increases CPU utilization by organizing jobs so that the CPU always has one to execute. switches occur so frequently that the users may interact with each program while it is running. Time-sharing systems were developed to provide ...
What is an Operating System?
... “The one program running at all times on the computer” is the kernel. Everything else is either a system program (ships with the operating system) or an application program ...
... “The one program running at all times on the computer” is the kernel. Everything else is either a system program (ships with the operating system) or an application program ...
OPERATING SYSTEM CONCEPTS Avi Silberschatz Department of
... Given that I/O instructions are privileged, how does the user program perform I/O? System call − the method used by a process to request action by the operating system. - Usually takes the form of a trap to a specific location in the interrupt vector. - Control passes through the interrupt vector to ...
... Given that I/O instructions are privileged, how does the user program perform I/O? System call − the method used by a process to request action by the operating system. - Usually takes the form of a trap to a specific location in the interrupt vector. - Control passes through the interrupt vector to ...
Solution Operating System Concepts By Galvin,Silberschatz Solved
... The primary difference is that kernel-level context switches involve execution of OS code. As such it requires crossing the boundary between user- and kernel-land two times. When the kernel is switching between two different address spaces it must store the registers as well as the address space. Sa ...
... The primary difference is that kernel-level context switches involve execution of OS code. As such it requires crossing the boundary between user- and kernel-land two times. When the kernel is switching between two different address spaces it must store the registers as well as the address space. Sa ...
2_threads
... Works, but unsatisfactory – This protects a single piece of “Critical-Section” code – Only protects for two threads – Thread 1’s code is different from Thread 2’s ...
... Works, but unsatisfactory – This protects a single piece of “Critical-Section” code – Only protects for two threads – Thread 1’s code is different from Thread 2’s ...
No Slide Title
... Executive — Process Manager Provides services for creating, deleting, and using ...
... Executive — Process Manager Provides services for creating, deleting, and using ...
Device controllers
... Used when device can service only one request at a time e.g., lock tape drive to particular process ...
... Used when device can service only one request at a time e.g., lock tape drive to particular process ...
(Silberschatz) I/O subsystems
... To cope with device transfer size mismatch To maintain “copy semantics” ...
... To cope with device transfer size mismatch To maintain “copy semantics” ...
ThreadsWinAndCpp11
... functions. This will cause exceptions. Worker threads communicate with a program’s windows by calling the Win32 API PostMessage and SendMessage functions. With modern GUI frameworks that is handled by calling Form.Invoke or Dispatcher.Invoke passing a delegate to the UI thread bound to a functio ...
... functions. This will cause exceptions. Worker threads communicate with a program’s windows by calling the Win32 API PostMessage and SendMessage functions. With modern GUI frameworks that is handled by calling Form.Invoke or Dispatcher.Invoke passing a delegate to the UI thread bound to a functio ...
Process Historian Administration
... sequence or group must therefore be divided into several "partitions" using the time axis. A partition includes runtime data for one or several time-variant value sequences that are limited by time values. The limited time values within a certain partition are referred to as "partition limitations". ...
... sequence or group must therefore be divided into several "partitions" using the time axis. A partition includes runtime data for one or several time-variant value sequences that are limited by time values. The limited time values within a certain partition are referred to as "partition limitations". ...
Deadlocks
... Requesti = request vector for process Pi. If Requesti [j] = k then process Pi wants k instances of resource type Rj 1. If Requesti Needi go to step 2. Otherwise, raise error condition, since process has exceeded its maximum claim 2. If Requesti Available, go to step 3. Otherwise Pi must wait, si ...
... Requesti = request vector for process Pi. If Requesti [j] = k then process Pi wants k instances of resource type Rj 1. If Requesti Needi go to step 2. Otherwise, raise error condition, since process has exceeded its maximum claim 2. If Requesti Available, go to step 3. Otherwise Pi must wait, si ...
Real-time Operating Systems
... • The scheduler is a central part of the kernel – executes periodically – executes when state of any thread changes ...
... • The scheduler is a central part of the kernel – executes periodically – executes when state of any thread changes ...
INF 5070 – Media Storage and Distribution Systems
... typically have soft deadlines (may miss a frame) are non-critical (user may be annoyed, but …) have periodic processing requirements (e.g., each 33 ms in a 30 fps video) ...
... typically have soft deadlines (may miss a frame) are non-critical (user may be annoyed, but …) have periodic processing requirements (e.g., each 33 ms in a 30 fps video) ...
Memory Mapped Files
... locate a block large enough for the allocation, mark it as allocated and return a pointer to it. Algorithms to locate a block include "first fit", "best fit" "quick fit“ and “buddy”. “First fit“ is the simplest: the list of free blocks is scanned until a free block large enough to satisfy the re ...
... locate a block large enough for the allocation, mark it as allocated and return a pointer to it. Algorithms to locate a block include "first fit", "best fit" "quick fit“ and “buddy”. “First fit“ is the simplest: the list of free blocks is scanned until a free block large enough to satisfy the re ...
Deadlock
... problem of deadlock by limiting access to resources and imposing restrictions on processes. They are conservative in nature. Deadlock detection approaches grant resource requests whenever possible. Periodically, an algorithm that detects the circular wait condition is performed and recovery is attem ...
... problem of deadlock by limiting access to resources and imposing restrictions on processes. They are conservative in nature. Deadlock detection approaches grant resource requests whenever possible. Periodically, an algorithm that detects the circular wait condition is performed and recovery is attem ...
VirtualMachines
... eventually passed to guest. Context Switches: VMM must save VM state when controlled transferred to VMM. Bookkeeping: VMM has to do work to simulate behavior of real machine, such as keeping track of time for VMs. Memory: Memory accesses may require access to both ...
... eventually passed to guest. Context Switches: VMM must save VM state when controlled transferred to VMM. Bookkeeping: VMM has to do work to simulate behavior of real machine, such as keeping track of time for VMs. Memory: Memory accesses may require access to both ...
