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Turnaround time (TAT) is the amount of time taken to complete a process or fulfill a request. [1] [2] The concept thus overlaps with lead time and can be contrasted with cycle time.
In computing, turnaround time is the total time taken between the submission of a program/process/thread/task (Linux) for execution and the return of the complete output to the customer/user. [3] It may vary for various programming languages depending on the developer of the software or the program. Turnaround time may simply deal with the total time it takes for a program to provide the required output to the user after the program is started.
Turnaround time is one of the metrics used to evaluate an operating system's scheduling algorithms. [4]
In case of batch systems, turnaround time will include time taken in forming batches, batch execution and printing results.
With increasing computerization of analytical instruments the distinction between a computing context and a "non-computing" context is becoming semantic. An example of a "non-computing" context of turnaround time is the time a particular analysis in a laboratory, such as a medical laboratory, other commercial laboratories or a public health laboratory takes to result. Laboratories may publish an average turnaround time to inform their clients, e.g. a health care worker ordering the test, after what time a result can be expected. A prolonged turnaround time may give the requester a clue that a specimen was not received, that an analysis met with problems within the lab including that the result was unusual, and the test was repeated for quality control. [2]
Lead Time vs Turnaround Time: Lead Time is the amount of time, defined by the supplier or service provider, that is required to meet a customer request or demand. [5] Lead-time is basically the time gap between the order placed by the customer and the time when the customer get the final delivery, on the other hand the Turnaround Time is in order to get a job done and deliver the output, once the job is submitted for processing center according to the customer request. [6]
Turnaround Time vs Response Time: Turnaround time is the amount of time elapsed from the time of submission to the time of completion whereas response time is the average time elapsed from submission until the first response is produced.
Turnaround Time vs Wait Time: Waiting time is amount of time a process has been waiting in the ready queue. [7]
Reasons of Delays: In case of warehouses, there are several reasons, due to which TAT can increase. First of all, if laborers or equipment are not working properly, and if the maximum efficiency could not be reached, the process would be delayed. Secondly, the infrastructure, improper infrastructure could be an obstacle for the TAT reduction.
In computing, multitasking is the concurrent execution of multiple tasks over a certain period of time. New tasks can interrupt already started ones before they finish, instead of waiting for them to end. As a result, a computer executes segments of multiple tasks in an interleaved manner, while the tasks share common processing resources such as central processing units (CPUs) and main memory. Multitasking automatically interrupts the running program, saving its state and loading the saved state of another program and transferring control to it. This "context switch" may be initiated at fixed time intervals, or the running program may be coded to signal to the supervisory software when it can be interrupted.
In computing, a context switch is the process of storing the state of a process or thread, so that it can be restored and resume execution at a later point, and then restoring a different, previously saved, state. This allows multiple processes to share a single central processing unit (CPU), and is an essential feature of a multiprogramming or multitasking operating system. In a traditional CPU, each process - a program in execution - utilizes the various CPU registers to store data and hold the current state of the running process. However, in a multitasking operating system, the operating system switches between processes or threads to allow the execution of multiple processes simultaneously. For every switch, the operating system must save the state of the currently running process, followed by loading the next process state, which will run on the CPU. This sequence of operations that stores the state of the running process and the loading of the following running process is called a context switch.
An operating system (OS) is system software that manages computer hardware and software resources, and provides common services for computer programs.
Real-time computing (RTC) is the computer science term for hardware and software systems subject to a "real-time constraint", for example from event to system response. Real-time programs must guarantee response within specified time constraints, often referred to as "deadlines".
Computerized batch processing is a method of running software programs called jobs in batches automatically. While users are required to submit the jobs, no other interaction by the user is required to process the batch. Batches may automatically be run at scheduled times as well as being run contingent on the availability of computer resources.
In computing, a process is the instance of a computer program that is being executed by one or many threads. There are many different process models, some of which are light weight, but almost all processes are rooted in an operating system (OS) process which comprises the program code, assigned system resources, physical and logical access permissions, and data structures to initiate, control and coordinate execution activity. Depending on the OS, a process may be made up of multiple threads of execution that execute instructions concurrently.
The CDC 6600 was the flagship of the 6000 series of mainframe computer systems manufactured by Control Data Corporation. Generally considered to be the first successful supercomputer, it outperformed the industry's prior recordholder, the IBM 7030 Stretch, by a factor of three. With performance of up to three megaFLOPS, the CDC 6600 was the world's fastest computer from 1964 to 1969, when it relinquished that status to its successor, the CDC 7600.
In computing, scheduling is the action of assigning resources to perform tasks. The resources may be processors, network links or expansion cards. The tasks may be threads, processes or data flows.
The von Neumann architecture—also known as the von Neumann model or Princeton architecture—is a computer architecture based on a 1945 description by John von Neumann, and by others, in the First Draft of a Report on the EDVAC. The document describes a design architecture for an electronic digital computer with these components:
In computing, time is a command in Unix and Unix-like operating systems. It is used to determine the duration of execution of a particular command.
In computing, a pipeline, also known as a data pipeline, is a set of data processing elements connected in series, where the output of one element is the input of the next one. The elements of a pipeline are often executed in parallel or in time-sliced fashion. Some amount of buffer storage is often inserted between elements.
In computing, preemption is the act of temporarily interrupting an executing task, with the intention of resuming it at a later time. This interrupt is done by an external scheduler with no assistance or cooperation from the task. This preemptive scheduler usually runs in the most privileged protection ring, meaning that interruption and then resumption are considered highly secure actions. Such changes to the currently executing task of a processor are known as context switching.
A job scheduler is a computer application for controlling unattended background program execution of jobs. This is commonly called batch scheduling, as execution of non-interactive jobs is often called batch processing, though traditional job and batch are distinguished and contrasted; see that page for details. Other synonyms include batch system, distributed resource management system (DRMS), distributed resource manager (DRM), and, commonly today, workload automation (WLA). The data structure of jobs to run is known as the job queue.
Takt time, or simply takt, is a manufacturing term to describe the required product assembly duration that is needed to match the demand. Often confused with cycle time, takt time is a tool used to design work and it measures the average time interval between the start of production of one unit and the start of production of the next unit when items are produced sequentially. For calculations, it is the time to produce parts divided by the number of parts demanded in that time interval. The takt time is based on customer demand; if a process or a production line are unable to produce at takt time, either demand leveling, additional resources, or process re-engineering is needed to ensure on-time delivery.
CPU time is the amount of time for which a central processing unit (CPU) was used for processing instructions of a computer program or operating system, as opposed to elapsed time, which includes for example, waiting for input/output (I/O) operations or entering low-power (idle) mode. The CPU time is measured in clock ticks or seconds. Often, it is useful to measure CPU time as a percentage of the CPU's capacity, which is called the CPU usage. CPU time and CPU usage have two main uses.
In computing, computer performance is the amount of useful work accomplished by a computer system. Outside of specific contexts, computer performance is estimated in terms of accuracy, efficiency and speed of executing computer program instructions. When it comes to high computer performance, one or more of the following factors might be involved:
In computer architecture, multithreading is the ability of a central processing unit (CPU) to provide multiple threads of execution concurrently, supported by the operating system. This approach differs from multiprocessing. In a multithreaded application, the threads share the resources of a single or multiple cores, which include the computing units, the CPU caches, and the translation lookaside buffer (TLB).
A process is a program in execution, and an integral part of any modern-day operating system (OS). The OS must allocate resources to processes, enable processes to share and exchange information, protect the resources of each process from other processes and enable synchronization among processes. To meet these requirements, the OS must maintain a data structure for each process, which describes the state and resource ownership of that process, and which enables the OS to exert control over each process.
A lightweight kernel (LWK) operating system is one used in a large computer with many processor cores, termed a parallel computer.
In software engineering, cycle time is a software metric which estimates development speed in (agile) software projects. The cycle time measures how long it takes to process a given job - whether it's a client request, an order, or a defined production process stage. The crucial aspect of measuring the cycle time is considering only the active, operating processing time and discarding any idle, waiting, or service times occurring mid-process.