Chapter08-OSedition7Final
... Each process has its own page table each page table entry contains the frame number of the corresponding page in main memory ...
... Each process has its own page table each page table entry contains the frame number of the corresponding page in main memory ...
Introduction - Stanford Secure Computer Systems Group
... (e.g., bring a page in from disk only when accessed) • CPU enforced read-only virtual addresses useful - E.g., allows sharing of code pages between processes - Plus many other optimizations • CPU enforced execute disable of VAs - Makes certain code injection attacks harder ...
... (e.g., bring a page in from disk only when accessed) • CPU enforced read-only virtual addresses useful - E.g., allows sharing of code pages between processes - Plus many other optimizations • CPU enforced execute disable of VAs - Makes certain code injection attacks harder ...
01-ch1_introduction_minor changes - pnu-cs-os
... In time-sharing systems, the CPU executes multiple jobs by switching among them, but the switches occur so frequently that the users can interact with each program while it is running. The CPU time is shared by different processes, so it is called as “Time sharing Systems”. Time slice is defined by ...
... In time-sharing systems, the CPU executes multiple jobs by switching among them, but the switches occur so frequently that the users can interact with each program while it is running. The CPU time is shared by different processes, so it is called as “Time sharing Systems”. Time slice is defined by ...
Operating System Structures
... − Resource allocation - When multiple users or multiple jobs running concurrently, resources must be allocated to each of them ...
... − Resource allocation - When multiple users or multiple jobs running concurrently, resources must be allocated to each of them ...
Windows - Part I
... •Applications reference “virtual address” •Page tables – hardware and software translators to physical address •Unit of protection and usage •Called page •X86 uses 4096 byte pages ...
... •Applications reference “virtual address” •Page tables – hardware and software translators to physical address •Unit of protection and usage •Called page •X86 uses 4096 byte pages ...
over view of operating system
... Process termination requires reclaim of any reusable resources Single-threaded process has one program counter specifying location of next instruction to execute Process executes instructions sequentially, one at a time, until completion Multi-threaded process has one program counter per thread Typi ...
... Process termination requires reclaim of any reusable resources Single-threaded process has one program counter specifying location of next instruction to execute Process executes instructions sequentially, one at a time, until completion Multi-threaded process has one program counter per thread Typi ...
Chapter 2 Operating System Overview Operating System Overview
... • Special type of programming language to control jobs • Provides instruction to the monitor – What compiler to use – What data to use ...
... • Special type of programming language to control jobs • Provides instruction to the monitor – What compiler to use – What data to use ...
Operating System Overview
... • Special type of programming language to control jobs • Provides instruction to the monitor – What compiler to use – What data to use ...
... • Special type of programming language to control jobs • Provides instruction to the monitor – What compiler to use – What data to use ...
Chapter 2Operating System Overview
... • Special type of programming language to control jobs • Provides instruction to the monitor – What compiler to use – What data to use ...
... • Special type of programming language to control jobs • Provides instruction to the monitor – What compiler to use – What data to use ...
CS 4410/4411 Systems Programming and Operating Systems
... • Multiprogramming systems increased utilization – Developed in the 1960s – Keeps multiple runnable jobs loaded in memory – Overlaps I/O processing of a job with computation of another – Benefits from I/O devices that can operate asynchronously – Requires the use of interrupts and DMA – Optim ...
... • Multiprogramming systems increased utilization – Developed in the 1960s – Keeps multiple runnable jobs loaded in memory – Overlaps I/O processing of a job with computation of another – Benefits from I/O devices that can operate asynchronously – Requires the use of interrupts and DMA – Optim ...
Memory Protection: Kernel and User Address Spaces
... Dynamic linking and shared libraries With dynamic loading, the actual memory used may not be large, but the executable size is large. A program must be statically linked with all libraries. Dynamic linking is conceptually similar to dynamic loading (except apply to linking) Postpone the lin ...
... Dynamic linking and shared libraries With dynamic loading, the actual memory used may not be large, but the executable size is large. A program must be statically linked with all libraries. Dynamic linking is conceptually similar to dynamic loading (except apply to linking) Postpone the lin ...
Test1_soln
... a. ULTs are cheaper to create and run than processes. b. Communication overhead between two ULTs is much smaller than between processes. c. ULTs are transparent to Kernel. Ans. (a) ULTs pertain to a single process, and therefore they share the same address space. Consequently, the overhead to create ...
... a. ULTs are cheaper to create and run than processes. b. Communication overhead between two ULTs is much smaller than between processes. c. ULTs are transparent to Kernel. Ans. (a) ULTs pertain to a single process, and therefore they share the same address space. Consequently, the overhead to create ...
A: Process termination requires reclaim of any reusable resources
... 1. Information in use copied from slower to faster storage temporarily 2. Faster storage (cache) checked first to determine if information is there: If it is, information used directly from the cache (fast) If not, data copied to cache and used there Q: Define a process? A: A process is a progra ...
... 1. Information in use copied from slower to faster storage temporarily 2. Faster storage (cache) checked first to determine if information is there: If it is, information used directly from the cache (fast) If not, data copied to cache and used there Q: Define a process? A: A process is a progra ...
- Suraj @ LUMS
... (What is an OS? Why is an OS Needed? Case study of the UNIX time-sharing OS.) ...
... (What is an OS? Why is an OS Needed? Case study of the UNIX time-sharing OS.) ...
Operating Systems
... by the processor’s bit-width. A 32-bit processor, like the Pentium IV, has 232 bytes or 4 GB of virtual memory. A 64-bit processor can have 264 bytes or 16 exabytes of virtual memory. Most desktop computers have 512 MB (229 bytes) of physical memory (RAM) or less. The operating system uses an area o ...
... by the processor’s bit-width. A 32-bit processor, like the Pentium IV, has 232 bytes or 4 GB of virtual memory. A 64-bit processor can have 264 bytes or 16 exabytes of virtual memory. Most desktop computers have 512 MB (229 bytes) of physical memory (RAM) or less. The operating system uses an area o ...
Overview of Operating Systems
... ❚ Timer Interrupts: Generated by a timer within the processor. This allows the operating system to perform certain functions on a regular basis, like scheduling ❚ Hardware Failure Interrupts: Generated by a failure (e.g. power failure or memory parity error). ...
... ❚ Timer Interrupts: Generated by a timer within the processor. This allows the operating system to perform certain functions on a regular basis, like scheduling ❚ Hardware Failure Interrupts: Generated by a failure (e.g. power failure or memory parity error). ...
Operating Systems I
... Controls use of main memory Allocates memory for each program and its data Reclaims memory when programs release it (or finish). Is supposed to know what areas are free. “Memory leak” manager loses track ...
... Controls use of main memory Allocates memory for each program and its data Reclaims memory when programs release it (or finish). Is supposed to know what areas are free. “Memory leak” manager loses track ...
Inside and Outside the OS
... Page table Keeps track of what is in memory and what is still out on hard disk Chapter 15 The Internal Operating System – Part 1 ...
... Page table Keeps track of what is in memory and what is still out on hard disk Chapter 15 The Internal Operating System – Part 1 ...
I/O devices
... – Reference bit (aka use bit) in PTE set to 1 on access to page – Periodically cleared to 0 by OS – A page with reference bit = 0 has not been used recently ...
... – Reference bit (aka use bit) in PTE set to 1 on access to page – Periodically cleared to 0 by OS – A page with reference bit = 0 has not been used recently ...
Chapter 3: Operating
... UNIX is a multitasking system. When a user logs on to the system, the shell (command interpreter) of the user’s choice is run. The shell may continue while another program is executed. To start a new process, the shell executes a fork system call. Then the selected program is loaded into memory ...
... UNIX is a multitasking system. When a user logs on to the system, the shell (command interpreter) of the user’s choice is run. The shell may continue while another program is executed. To start a new process, the shell executes a fork system call. Then the selected program is loaded into memory ...
Introduction to Computer and Operating Systems
... Caching – copying information into faster storage system; main memory can be viewed as a last cache for secondary storage ...
... Caching – copying information into faster storage system; main memory can be viewed as a last cache for secondary storage ...
Introduction to Computer and Operating Systems
... Caching – copying information into faster storage system; main memory can be viewed as a last cache for secondary storage ...
... Caching – copying information into faster storage system; main memory can be viewed as a last cache for secondary storage ...
Operating System
... OS itself whenever necessary. With continuing innovations, new architectures and compatible OSs are developed. But their details are not in the scope of this text since the objective here is to give only a general view about developments in OS concept. ...
... OS itself whenever necessary. With continuing innovations, new architectures and compatible OSs are developed. But their details are not in the scope of this text since the objective here is to give only a general view about developments in OS concept. ...