ppt
... A piece of code (library) is “thread-safe” if it defines critical sections and uses synchronization to control access to them All entry points must be re-entrant Results not returned in shared global variables nor global statically allocated storage All calls should be synchronous ...
... A piece of code (library) is “thread-safe” if it defines critical sections and uses synchronization to control access to them All entry points must be re-entrant Results not returned in shared global variables nor global statically allocated storage All calls should be synchronous ...
The following paper was originally published in the
... according to scheduling. A bound thread is one that permanently executes in the context of a light weight process in which no other threads can execute. Consequently, the bound thread is scheduled by the operating system kernel on a system wide basis. This is comparable to an NT thread. An unbound t ...
... according to scheduling. A bound thread is one that permanently executes in the context of a light weight process in which no other threads can execute. Consequently, the bound thread is scheduled by the operating system kernel on a system wide basis. This is comparable to an NT thread. An unbound t ...
Mac OS 8 Revealed
... You’ll discover a new computing landscape when you encounter Mac OS 8, the next major release of Apple Computer’s operating system—formerly code named Copland. This guide will acquaint you with the technical geography of Mac OS 8: its architecture, history, and special points of interest. ...
... You’ll discover a new computing landscape when you encounter Mac OS 8, the next major release of Apple Computer’s operating system—formerly code named Copland. This guide will acquaint you with the technical geography of Mac OS 8: its architecture, history, and special points of interest. ...
Notes on Operating Systems
... When a user application is running, the operating system loses its control over the machine. It regains control if the user application performs a system call, or if there is a hardware interrupt. Exercise 1 How can the operating system guarantee that there will be a system call or interrupt, so tha ...
... When a user application is running, the operating system loses its control over the machine. It regains control if the user application performs a system call, or if there is a hardware interrupt. Exercise 1 How can the operating system guarantee that there will be a system call or interrupt, so tha ...
slides-4
... utilization that forms the basis of multithreaded computer systems To discuss the APIs for the Pthreads thread libraries To explore several strategies that provide implicit threading To examine issues related to multithreaded programming To cover operating system support for threads in Windo ...
... utilization that forms the basis of multithreaded computer systems To discuss the APIs for the Pthreads thread libraries To explore several strategies that provide implicit threading To examine issues related to multithreaded programming To cover operating system support for threads in Windo ...
OS course notes - CS
... When a user application is running, the operating system loses its control over the machine. It regains control if the user application performs a system call, or if there is a hardware interrupt. Exercise 1 How can the operating system guarantee that there will be a system call or interrupt, so tha ...
... When a user application is running, the operating system loses its control over the machine. It regains control if the user application performs a system call, or if there is a hardware interrupt. Exercise 1 How can the operating system guarantee that there will be a system call or interrupt, so tha ...
Java Threads - Users.drew.edu
... • What do I mean by unit of execution? • In Java, concurrent programming is mostly concerned with threads. • However, processes are also important. ...
... • What do I mean by unit of execution? • In Java, concurrent programming is mostly concerned with threads. • However, processes are also important. ...
Operating Systems Principles and Programming More Contact
... Multiple Execution Flows Within a process, the program “spawns” multiple execution flows operating within the same address space: the threads Motivation I ...
... Multiple Execution Flows Within a process, the program “spawns” multiple execution flows operating within the same address space: the threads Motivation I ...
xv6 - PDOS-MIT
... and to provide a more useful set of services than the hardware alone supports. The operating system manages and abstracts the low-level hardware, so that, for example, a word processor need not concern itself with which type of disk hardware is being used. It also multiplexes the hardware, allowing ...
... and to provide a more useful set of services than the hardware alone supports. The operating system manages and abstracts the low-level hardware, so that, for example, a word processor need not concern itself with which type of disk hardware is being used. It also multiplexes the hardware, allowing ...
Concepts in Real-Time Operating Systems
... prevents a page from being swapped from memory to hard disk. In the absence of memory locking feature, memory access times of even critical real-time tasks can show large jitter, as the access time would greatly depend on whether the required page is in the physical memory or has been swapped out. M ...
... prevents a page from being swapped from memory to hard disk. In the absence of memory locking feature, memory access times of even critical real-time tasks can show large jitter, as the access time would greatly depend on whether the required page is in the physical memory or has been swapped out. M ...
Quick UNIX Tutorial
... Access rights on directories. r: allows users to list files in the directory; w: means that users may delete files from the directory or move files into it. Never give write permission to others to your home directory or any of its subdirectories. x: means the right to access files in the d ...
... Access rights on directories. r: allows users to list files in the directory; w: means that users may delete files from the directory or move files into it. Never give write permission to others to your home directory or any of its subdirectories. x: means the right to access files in the d ...
chapter 1 - University of Virginia
... The trend in microprocessor architecture is to exploit parallelism in hardware (Heuring). Microprocessors commonly use an assembly-line type approach to process instructions, where many different instructions are in various stages of completion. This technique is called pipelining. The fetch-execute ...
... The trend in microprocessor architecture is to exploit parallelism in hardware (Heuring). Microprocessors commonly use an assembly-line type approach to process instructions, where many different instructions are in various stages of completion. This technique is called pipelining. The fetch-execute ...
Before You Begin: Assign Information Classification
... IT Essentials: PC Hardware and Software v4.0 ...
... IT Essentials: PC Hardware and Software v4.0 ...
Threads
... Linux Threads Linux refers to them as tasks rather than threads Thread creation is done through clone() system call clone() allows a child task to share the address space ...
... Linux Threads Linux refers to them as tasks rather than threads Thread creation is done through clone() system call clone() allows a child task to share the address space ...
File - Computer Networks & Information Security
... At least 128 KB of nonvolatile memory is necessary to run Mobile Information Device (MID), and 8KB of nonvolatile memory is needed for storage of persistent application data. To run JVM, 32KB of volatile memory must be available. The device must also provide two-way network connectivity. b) Minimal ...
... At least 128 KB of nonvolatile memory is necessary to run Mobile Information Device (MID), and 8KB of nonvolatile memory is needed for storage of persistent application data. To run JVM, 32KB of volatile memory must be available. The device must also provide two-way network connectivity. b) Minimal ...
November 10 Lecture Slides
... Location – pointer to file location on device" Size – current file size" Protection – controls who can do reading, writing, executing" Time, date, and user identification – data for protection, security, and ...
... Location – pointer to file location on device" Size – current file size" Protection – controls who can do reading, writing, executing" Time, date, and user identification – data for protection, security, and ...
9. File Systems and I/O Management
... (to be more precise) a file from a directory simply amounts to deleting the directory entry that points to the inode, and need not always result in the file being scrubbed from the disk. When multiple hard links exist to a file/inode from multiple directories, unlinking a file from one of the direct ...
... (to be more precise) a file from a directory simply amounts to deleting the directory entry that points to the inode, and need not always result in the file being scrubbed from the disk. When multiple hard links exist to a file/inode from multiple directories, unlinking a file from one of the direct ...
the thread - Bilkent University Computer Engineering Department
... Many library procedures may not be reentrant. – They are not designed to have a second call to itself from the same process before it is completed (not re-entrant). • (We are talking about non-recursive procedures.) – They may be using global variables. Hence may not be thread-safe. ...
... Many library procedures may not be reentrant. – They are not designed to have a second call to itself from the same process before it is completed (not re-entrant). • (We are talking about non-recursive procedures.) – They may be using global variables. Hence may not be thread-safe. ...
Threads and Events
... degradation in performance, rather than an improvement. • Lastly, threads sometimes block. For example, if a thread is waiting for user input, it won’t do any further computation until it gets the input. A thread may also be waiting for a resource being used by another thread. If we are not careful, ...
... degradation in performance, rather than an improvement. • Lastly, threads sometimes block. For example, if a thread is waiting for user input, it won’t do any further computation until it gets the input. A thread may also be waiting for a resource being used by another thread. If we are not careful, ...
Operating System Fundamentals
... In the computer layer system the user interacts directly with software applications. The applications interact with both the user and the operating system. The operating system interacts with the applications and controls the hardware. Each layer is isolated and only interacts directly with the laye ...
... In the computer layer system the user interacts directly with software applications. The applications interact with both the user and the operating system. The operating system interacts with the applications and controls the hardware. Each layer is isolated and only interacts directly with the laye ...
Library (computing)
In computer science, a library is a collection of non-volatile resources used by computer programs, often to develop software. These may include configuration data, documentation, help data, message templates, pre-written code and subroutines, classes, values or type specifications. In IBM's OS/360 and its successors they are referred to as partitioned data sets.In computer science, a library is a collection of implementations of behavior, written in terms of a language, that has a well-defined interface by which the behavior is invoked. This means that as long as a higher level program uses a library to make system calls, it does not need to be re-written to implement those system calls over and over again. In addition, the behavior is provided for reuse by multiple independent programs. A program invokes the library-provided behavior via a mechanism of the language. For example, in a simple imperative language such as C, the behavior in a library is invoked by using C's normal function-call. What distinguishes the call as being to a library, versus being to another function in the same program, is the way that the code is organized in the system. Library code is organized in such a way that it can be used by multiple programs that have no connection to each other, while code that is part of a program is organized to only be used within that one program. This distinction can gain a hierarchical notion when a program grows large, such as a multi-million-line program. In that case, there may be internal libraries that are reused by independent sub-portions of the large program. The distinguishing feature is that a library is organized for the purposes of being reused by independent programs or sub-programs, and the user only needs to know the interface, and not the internal details of the library.The value of a library is the reuse of the behavior. When a program invokes a library, it gains the behavior implemented inside that library without having to implement that behavior itself. Libraries encourage the sharing of code in a modular fashion, and ease the distribution of the code. The behavior implemented by a library can be connected to the invoking program at different program lifecycle phases. If the code of the library is accessed during the build of the invoking program, then the library is called a static library. An alternative is to build the executable of the invoking program and distribute that, independently from the library implementation. The library behavior is connected after the executable has been invoked to be executed, either as part of the process of starting the execution, or in the middle of execution. In this case the library is called a dynamic library. A dynamic library can be loaded and linked as part of preparing a program for execution, by the linker. Alternatively, in the middle of execution, an application may explicitly request that a module be loaded.Most compiled languages have a standard library although programmers can also create their own custom libraries. Most modern software systems provide libraries that implement the majority of system services. Such libraries have commoditized the services which a modern application requires. As such, most code used by modern applications is provided in these system libraries.