CS 519 -- Operating Systems -
... Most processors support at least two modes of execution for protection reasons Privileged - kernel-mode Non-privileged - user-mode ...
... Most processors support at least two modes of execution for protection reasons Privileged - kernel-mode Non-privileged - user-mode ...
7.3. Computer System Structures
... known as the bootstrap program or bootstrap loader locates the kernel, loads it into main memory, and starts its execution. Some computer systems, such as PCs, use a two-step process in which a simple bootstrap loader fetches a more complex boot program from disk, which in turn loads the kernel. Whe ...
... known as the bootstrap program or bootstrap loader locates the kernel, loads it into main memory, and starts its execution. Some computer systems, such as PCs, use a two-step process in which a simple bootstrap loader fetches a more complex boot program from disk, which in turn loads the kernel. Whe ...
DeadLocks
... When a process requests an available resource, system must decide if immediate allocation leaves the system in a safe state. System is in safe state if there exists a safe sequence of all processes. ...
... When a process requests an available resource, system must decide if immediate allocation leaves the system in a safe state. System is in safe state if there exists a safe sequence of all processes. ...
No Slide Title
... to restore the disk to a consistent state with minimal data loss. This feature is called Fault Tolerance. ...
... to restore the disk to a consistent state with minimal data loss. This feature is called Fault Tolerance. ...
Machine and Operating System Organization
... LPOVERLAPPED ovl—indicates if overlapped I/O is being used ...
... LPOVERLAPPED ovl—indicates if overlapped I/O is being used ...
Introduction to Operating Systems
... Special instruction transfers control to kernel . . . which dispatches to one of few hundred syscall handlers ...
... Special instruction transfers control to kernel . . . which dispatches to one of few hundred syscall handlers ...
Virtual Machine Monitors
... software mode bit: During a system call, switch to “kernel” mode On system call return, switch to “user” mode ...
... software mode bit: During a system call, switch to “kernel” mode On system call return, switch to “user” mode ...
Processes and Resources Operating System Control Structures
... (LIFO) system stacks associated with it. A stack is used to store parameters and calling addresses for procedure and system calls. The stack pointer points to the top of the stack. ...
... (LIFO) system stacks associated with it. A stack is used to store parameters and calling addresses for procedure and system calls. The stack pointer points to the top of the stack. ...
Lecture #19: Storage Management
... Provides a set of remote procedure calls for remote file operations. The procedures support the following operations ...
... Provides a set of remote procedure calls for remote file operations. The procedures support the following operations ...
Operating Systems CIS 250
... • A unit of work in a time-sharing system • Even if only one program is executing, the O/S has internal processes executing • Process execution is sequential: one instruction at a time • Made up of program code, program counter value (indicates current activity), registers, stack (temp. info: variab ...
... • A unit of work in a time-sharing system • Even if only one program is executing, the O/S has internal processes executing • Process execution is sequential: one instruction at a time • Made up of program code, program counter value (indicates current activity), registers, stack (temp. info: variab ...
Operating-System - Jyoti Computer Centre
... operating system called…….that modularized the kernel using the micro kernel approach. This method structure the operating system by removing all …………. components from the ……………. And implementing then as system and ……………… programs. a) Mach, Non-essential, Kernel, User-level. b) Macintosh, Essential, ...
... operating system called…….that modularized the kernel using the micro kernel approach. This method structure the operating system by removing all …………. components from the ……………. And implementing then as system and ……………… programs. a) Mach, Non-essential, Kernel, User-level. b) Macintosh, Essential, ...
Slide set 14
... context switch occurs. The state of the current process is saved in it’s pcb, and the cpu is loaded with the context of the new running process. Context switches are pure overhead – there is no useful work done during a context switch. ...
... context switch occurs. The state of the current process is saved in it’s pcb, and the cpu is loaded with the context of the new running process. Context switches are pure overhead – there is no useful work done during a context switch. ...
Operating Systems
... • e.g. Windows NT was originally microkernel (3.5), but now (4.0 onwards) pushed lots back into kernel for performance. • Still not clear what the best OS structure is, or how much it really matters. . . ...
... • e.g. Windows NT was originally microkernel (3.5), but now (4.0 onwards) pushed lots back into kernel for performance. • Still not clear what the best OS structure is, or how much it really matters. . . ...
Lecture3-os-support
... The Role of the OS • The operating system needs to provide support for implementation of distributed systems • We will look at how distributed systems services interact with the operating systems • We will discuss the support that the operating system needs to provide ...
... The Role of the OS • The operating system needs to provide support for implementation of distributed systems • We will look at how distributed systems services interact with the operating systems • We will discuss the support that the operating system needs to provide ...
process
... • Inter-Process Communication or IPC – would like two processes to share information between them • shared file • split a single application into multiple processes to speed up execution by allowing overlapped I/O • split an application into multiple processes for modularity of coding ...
... • Inter-Process Communication or IPC – would like two processes to share information between them • shared file • split a single application into multiple processes to speed up execution by allowing overlapped I/O • split an application into multiple processes for modularity of coding ...
PPT
... I/O operations - A running program may require I/O, which may involve a file or an I/O device. ...
... I/O operations - A running program may require I/O, which may involve a file or an I/O device. ...
Lecture-2
... Timesharing (multitasking) is logical extension in which CPU switches jobs so frequently that users can interact with each ...
... Timesharing (multitasking) is logical extension in which CPU switches jobs so frequently that users can interact with each ...
Operating System Structures
... of the bare hardware . A virtual machine provides an interface identical to the underlying bare hardware. The operating system creates the illusion of multiple processes, each executing on its own processor with its own (virtual) memory. Virtual Machine: A machine implemented in software, not ...
... of the bare hardware . A virtual machine provides an interface identical to the underlying bare hardware. The operating system creates the illusion of multiple processes, each executing on its own processor with its own (virtual) memory. Virtual Machine: A machine implemented in software, not ...
UNIT 1
... I/O operations – since user programs cannot execute I/O operations directly, the operating system must provide some means to perform I/O. File-system manipulation – program capability to read, write, create, and delete files. Communications – exchange of information between processes executing eithe ...
... I/O operations – since user programs cannot execute I/O operations directly, the operating system must provide some means to perform I/O. File-system manipulation – program capability to read, write, create, and delete files. Communications – exchange of information between processes executing eithe ...
ch04
... Direct Communication Processes must name each other explicitly: send (P, message) – send a message to process P receive(Q, message) – receive a message from ...
... Direct Communication Processes must name each other explicitly: send (P, message) – send a message to process P receive(Q, message) – receive a message from ...
Operating Systems: Process Management
... Other UNIX commands top – process list, continuously updated jobs – list jobs running in current shell bg, fg – send jobs to back/foreground at – run batch job at specified time(s) kill – send signal to terminate process sleep – pause for some seconds 27 March 2003 ...
... Other UNIX commands top – process list, continuously updated jobs – list jobs running in current shell bg, fg – send jobs to back/foreground at – run batch job at specified time(s) kill – send signal to terminate process sleep – pause for some seconds 27 March 2003 ...
CHAP10
... – control over task priorities and rights – user should be able to distinguish between hard and soft tasks and to specify relative priorities within each class – May allow user to specify such characteristics as: ...
... – control over task priorities and rights – user should be able to distinguish between hard and soft tasks and to specify relative priorities within each class – May allow user to specify such characteristics as: ...
Course Intro
... student members. ACM membership is $18/year for EMU students. Check the note on ACM membership. There are many free-to-members ACM Books and ACM Courses over the Web on OS theory, practices and various OSs. Check TOP TEN courses of the last month. ...
... student members. ACM membership is $18/year for EMU students. Check the note on ACM membership. There are many free-to-members ACM Books and ACM Courses over the Web on OS theory, practices and various OSs. Check TOP TEN courses of the last month. ...