The main use of virtual memory is, it allows the users to use more memory for applications/programs/tasks than the available physical memory (RAM) on the system. Cookie Preferences Hardware-assisted Trusted Memory Disaggregation for Secure Far Memory . After complition of one program, another program may start. The SlideShare family just got bigger. This type of memory management ensures the availability of adequate memory for the program's objects and data structures. By accepting, you agree to the updated privacy policy. 4.2 Swapping Pre-cleaning also improves responsiveness. The main aim of memory management is to achieve efficient utilization of memory. The instruction will contain address for memory locations of two types: These addresses will change each time a process is swapped in. Looks like youve clipped this slide to already. Segment table consumes less space in comparison with a page table. Programs and services are assigned with a specific memory as per their requirements when they are executed. 4.8 Segmentation. When processes are loaded and removed from the memory, the free space, which they occupied, is broken into little pieces, casing external fragmentation. While the operating system is in control, it decides which process in the queue sholud be executed next. The Little Man Computer (LMC) is a software simulator of a simple computer with a CPU, memory, and a basic instruction set. Virtual memory is a peripheral in the operating system, which enables a computer to be able to compensate shortages of physical memory (RAM) by transferring pages of data from Random Access Memory (RAM) to disk storage to deny overloading, furthermore virtual memory is designed to work temporary in combination with RAM. It deals with memory and the moving of processes from disk to primary memory for execution and back again. by 2.Ready : https://brainly.in/question/3197766#:~:text=Dirty%20pages%20are%20the%20pages,disk%20is%20altered%20or%20appended. we also have provided the depth knowledge of some topics which really require more words to explain. Vishal Singh Follow software development consultant Advertisement Advertisement Recommended Paging and segmentation Piyush Rochwani 62.6k views 32 slides Memory management ppt ManishaJha43 733 views 64 slides Virtual memory Anuj Modi 34.8k views 15 slides One of the main problems associated with memory management is: Memory leaks. The segments can be moved in and out of the memory as required, meaning they dont have to be stored continuously across a fixed address space. (A) [Type here] List of Practical/ Experiments: Practical Number Type of Experiment Practical/ Experiment Topic Hrs. 5.Exit : The process has terminated and will be destroyed by the operating system. It does this by moving information back and forth between primary memory and secondary memory by using the concept of swapping. Salesforce Customer 360 is a collection of tools that connect Salesforce apps and create a unified customer ID to build a single All Rights Reserved, Memory manager permits computers with a small amount of main memory to execute programs larger than the size or amount of available memory. personal computer: a small, single-user computer. @ n ? " The processor alternates between executing operating system instructions and executing user processes. The basic architecture has the CPU at the . In data communications, a gigabit (Gb) is 1 billion bits, or 1,000,000,000 (that is, 10^9) bits. Since process-4 is smaller then process-2, another hole is created. Now customize the name of a clipboard to store your clips. 2018. Activate your 30 day free trialto continue reading. The process is being executed by the processor. Activate your 30 day free trialto unlock unlimited reading. Segmented paged memory Segmentation is used to describe logical memory division subject to access control, and paging can handle the allocation of memory inside the partitions. 4.6 Design issues for paging systems What is control of Register and Memory in Computer Architecture? 66 modules covering EVERY Computer Science topic needed for A-Level. [1] LegoOS A Disseminated Distributed OS for Hardware Resource Disaggregation Yizhou Shan, Yutong Huang, Yilun Chen, and . FIFO may result in poor efficiency, though because some of the pages that were removed may be in frequent use, there removal from memory will result in additional page faults being generated. Lecture 1: CS/ECE 3810 Introduction Today's topics: Why computer organization is important Logistics Modern trends * Type It can determine between multiple types of segments and denotes the access attributes. If memory demand exceeds the physical memory's capacity, the OS can automatically allocate virtual memory to a process as it would physical memory. | Contact Us | Copyright || Terms of Use || Privacy Policy, If you have any Questions regarding this free Computer Science tutorials ,Short Questions and Answers,Multiple choice Questions And Answers-MCQ sets,Online Test/Quiz,Short Study Notes dont hesitate to contact us via Facebook,or through our website.Email us @, Download Computer Organization and Architecture Memory Management PDF File, Copyright || Terms of Use || Privacy Policy. Foundations of Python Network Programming - John . Ultimately memory management will depend on the how effective the configuration is in the hardware, operating system, and programs or applications. Logical address is expressed as a location relative to the beginning of the program. The more virtual memory thats being used, the less disk space a user has for storage. To learn concepts behind advanced pipelining techniques. FIFO replaces the page, which has been in memory for the longest time, though it based that the page is unlikely to be in use. Why Memory Management is required: The operating system swaps out process-2 which leaves sufficient room for new process of size 320-KB. % ) , . These addresses are used as a reference to access the physical memory location by the CPU. The OS is also responsible for handling processes when the computer runs out of physical memory space. Key idea #2: caching! Agree Therefore, when RAM runs close to full capacity, virtual memory can move data from the RAM to a space which is referred to as a paging file. The page at the top of the list is removed, and the new page is added to the back of the list. Retrieved 2012-08-20. What is shared-memory model in computer architecture? As we know that memory is that which stores the programs and these programs are used by the CPU for processing. Vishal Singh Definition: Computer Organization and Architecture is the study of internal working, structuring and implementation of a computer system. Google Scholar Digital Library; J. Li, G. Yan, W. Lu, S. Jiang, S. Gong, J. Wu, and X. Li. 45 modules covering EVERY Computer Science topic needed for GCSE level. For paged system, this bit is constantly set to 1. 2. It is a large and fast memory used to store data during computer operations. Some memory management architectures allow each process to have its own area or configuration of the page table, with a mechanism to switch between different mappings on a process switch. - A free PowerPoint PPT presentation (displayed as an HTML5 slide show) on PowerShow.com - id: 3e9eab-YzU0O 0000\ F 00 0=] 00 000 2 3 !! D/B bit In a code segment, this is the D bit and denotes either operands or addressing modes are 16 or 32 bits. It must take input from some input device and place the result in some output device. Due to the speed mismatch of the processor and I/O device, the status at any point in time is reffered to as a state. Now customize the name of a clipboard to store your clips. Computer Organization and Architecture MCQs. If u need a hand in making your writing assignments - visit www.HelpWriting.net for more detailed information. To understand the "hitting the memory wall" problem and the current state-of-art in memory system design. Computer Organization & Architecture 7e - Stallings 2008-02 Operating Systems - Andrew S. Tanenbaum 2009 . The process waiting for some I/O to complete, must stored back in disk. We make use of First and third party cookies to improve our user experience. Physical and Virtual Memory Physical memory presents a flat address space Addresses 0 to 2 p -1 p = number of bits in an address word, PowerPoint presentation 'Computer Architecture Memory Management Units' is the property of its rightful owner. When a logical address is split, it is divided into memory units which referred to as pages, furthermore, when this page is loaded into main memory, it is stored in a page frame, which is a block of sequential addresses that are the same size (meaning they have the same number of addresses) as the page. In paging, a process address is broken into fixed sized blocks called pages, In segmentation, an address is space is broken into a varying sized blocks called sections, Operating system divides the memory into pages, The compiler is responsible to calculate the segment size, the virtual address and actual address, Page size is ultimately determined by the available memory, Paging is faster in terms of memory access, Segmentation as a whole is slower than paging, May cause internal fragmentation as some pages may go underutilsied, May cause external fragmentation as some of the memory block may not be used at all, Logical address is divided into page number and page offset, Logical address is divided into section number and section offset, Segmentation table stores the segmented data, An editable PowerPoint lesson presentation, A glossary which covers the key terminologies of the module, Topic mindmaps for visualising the key concepts, Printable flashcards to help students engage active recall and confidence-based repetition, A quiz with accompanying answer key to test knowledge and understanding of the module. Less input/output is required, which leads to faster and easy swapping of processes. Dirty page: A dirty page in an operating system refers to pages in memory (page cache) that has been rationalised and therefore it has changed for what is currently stored on the disk. When that happens, the OS turns to virtual memory, a type of pseudo-memory allocated from a storage drive that's been set up to emulate the computer's main memory. 4.5 Modeling page replacement algorithms Instructions in the program contains only logical address. If it is suspended because the process requests I/O, then it is places in the appropriate I/O queue. But swapping is an I/O process, so it also takes time. The speed of the main memory is very low in comparison with the speed of modern processors. In a uni-programming system, the program currently being executed is loaded into the user part of the memory. Interfacing of devices for I/O, memory and memory management. (Linked list: In computer science a linked list refers to a linear data structure where each element is a separate object, though the elements in a linked list are not stored in at a contiguous location, these elements are lined using pointers.). Over 5,000 teachers have signed up to use our materials in their classroom. the process starts by first identifying the problem and finding different issues that can cause such a problem and eventually leading to implementing a solution or alternative. But, this is not the only hole that will be present in variable size partition. At some point none of the process in main memory is ready. : ; ? ] Furthermore the operating system has to map the logical address space to the physical address space and manage memory usage between the processes as appropriate, for instance via segmentation, paging, or the use of virtual memory. Excellent communication (written, oral), presentation, and documentation skills. Enjoy access to millions of ebooks, audiobooks, magazines, and more from Scribd. Memory management resides in hardware , in the OS (operating system), and in programs and applications . Different levels of memory Some are small & fast Others are large & slow What levels are usually included? A data lifecycle is the sequence of stages that a particular unit of data goes through from its initial generation or capture to its eventual archival and/or deletion at the end of its useful life. Introduction to digital design. Description. Tap here to review the details. Copyright 1999 - 2023, TechTarget Memory management is the process of controlling and coordinating a computer's main memory. Figure: The effect of dynamic partitioning, For Offline Study you can Download pdf file from below link Customer success is a strategy to ensure a company's products are meeting the needs of the customer. Demand paging as it says from the title, only copies data from the disk to the RAM if the data is required by some program, therefore meaning that the data will not be when the data is already available on the memory. External fragmentation occurs when theres a sufficient quantity of area within the memory to satisfy the memory request of a method, though the processs memory request cannot be fulfilled because the memory offered is during a non-contiguous manner. C It appears that you have an ad-blocker running. When a process is brought into memory, it is allocated exactly as much memory as it requires and no more. $.' a hh88 The software consists of a set of instructions that instruct the computer to perform a task. Unsegmented unpaged memory In this case, the virtual address is the equivalent of the physical address. When memory holds multiple processes, then the process can move from one process to another process when one process is waiting. Activate your 30 day free trialto unlock unlimited reading. Privacy Policy Since the size of main memory is fixed, it is possible to accomodate only few process in the main memory. One of the MMU's most important roles is to translate the logical addresses used by the running processes to the physical addresses on the memory devices. Virtual Memory ; It is an addressing scheme implemented in hardware and software that allows non-contiguous memory to be addressed as if it is contiguous ; Protection ; Many operating systems support protection of memory pages . A Memory Management Hardware provides the mapping between logical and physical view. Most likely we will not get two process of same size. This expression covers all related hardware components (wire, optical fiber, etc.) https://www.interviewbit.com/courses/programming/topics/linked-lists/#:~:text=A%20linked%20list%20is%20a,has%20a%20reference%20to%20null. The operating system, programs, applications, and hardware all have memory management systems. This technique will minimise the amount of cleaning that is needed to obtain a new page frame, which is needed at the moment a new program initiates or a new data file is opened. . The topics are explained from a programmer's point of view, and the text emphasizes consequences for . Operating System-Memory ",#(7),01444'9=82. Automatic memory management is a mechanism, in which an operating system or application automatically manages the allocation and deallocation of memory. Use of interrupt in 8051. The task of the subdivision is carried out dynamically by the operating framework and is called memory management. By accepting, you agree to the updated privacy policy. For example, a process that require 5-MB of memory would be placed in the 6-MB partition which is the smallest available partition. Instruction Set Architectures An instruction set architecture (ISA) has been defined as: the attributes of a [computing] system as seen by the programmer, i.e. The clock algorithm can be recognised to be a variation of the FIFO algorithm, though the difference is that a circular linked list is used and that each entry in the list has a page referenced bit, which is initially set to 0, and it is set to 1 each time the page will be referenced. the conceptual structure and functional behavior, as distinct from the organization of the data flows and controls the logic design, and the physical implementation. By whitelisting SlideShare on your ad-blocker, you are supporting our community of content creators. This allows the RAM on the system to free up space so that the computer can continue with the main execution/task. If all are waiting for I/O operation, then again CPU remains idle. Swapped out a block process to intermediate queue of blocked process. If it is suspended because of a timeout or because the operating system must attend to processing some of its task, then it is placed in ready state. Memory leaks are a failure in the program to release discarded memory, which will cause either a decrease in performance and ultimately failure. Direct Memory Access . To accommodate the allocation process, the OS continuously moves processes between memory and storage devices (hard disk or SSD), while tracking each memory location and its allocation status. Granularity bit (G) It denotes either the limit field is to be disrupted in units by one byte or 4K bytes. Memory management is an activity, which is carried out in the kernel of the operating system. Subject - Computer Organization and ArchitectureVideo Name - Memory Management HardwareChapter - Memory OrganizationFaculty - Anil PrasadUpskill and get Placements with Ekeeda Career TracksData Science - https://ekeeda.com/career-track/data-scientistSoftware Development Engineer - https://ekeeda.com/career-track/software-development-engineerEmbedded and IOT Engineer - https://ekeeda.com/career-track/embedded-and-iot-engineerGet FREE Trial for GATE 2023 Exam with Ekeeda GATE - 20000+ Lectures \u0026 Notes, strategy, updates, and notifications which will help you to crack your GATE exam.https://ekeeda.com/catalog/competitive-examCoupon Code - EKGATEGet Free Notes of All Engineering Subjects \u0026 Technologyhttps://ekeeda.com/digital-libraryAccess the Complete Playlist of Subject Computer Organisation and Architecture - https://youtube.com/playlist?list=PLm_MSClsnwm_glYmBNVsz1f5tdr69_NlUHappy LearningSocial Links:https://www.instagram.com/ekeeda_official/https://in.linkedin.com/company/ekeeda.com#computerArchitecture#MemoryOrganization #ComputerOrganisationandArchitecture In addition to the. 4.7 Implementation issues It ensures that blocks of memory space are properly managed and allocated so the operating system (OS), applications and other running processes have the memory they need to carry out their operations. Therefore, memory management is an important issue while designing a computer system. By using this website, you agree with our Cookies Policy. Dan Stefanica - A Primer for the Mathematics of Financial Engineering-FE Pres FAZAIA RUTH PFAU MEDICAL COLLEGE ,KARACHI,PAKISTAN, breaking through the language barrier.docx, break even net present internal rate of return.docx, 17- Parameterize Pipelines in Azure Data Factory.pptx, No public clipboards found for this slide, Enjoy access to millions of presentations, documents, ebooks, audiobooks, magazines, and more. A sequential search is performed in the memory using the specified key to find out the matching key from the memory. When a new page requires to be brought into memory for the specific process/applications/task, it will be often necessary to remove one that is currently already there. Memory management strives to optimize memory usage so the CPU can efficiently access the instructions and data it needs to execute the various processes. The SlideShare family just got bigger. Collection of such software programs are basically known as operating systems. Dirty bit This bit is set to 1 by the processor when a write operation to the corresponding page appears. In most cases, a process will not require exactly as much memory as provided by the partition. To utilize the idle time of CPU, we are shifting the paradigm from uniprogram environment to multiprogram environment. scheduling, I/O, deadlocks, memory management, threads, file systems, security, and more. First of all we have to keep all the information in some storage, mainly known as main memory, and CPU interacts with the main memory only. Hardware: At hardware level, memory management involves physical devices that store the data. During the execution of process, a process may be swapped in or swapped out many times. As part of this operation, an OS might use swapping to accommodate more processes. The pointer of the linked list moves around the list until a page frame with a page referenced bit of 0 is found (if all the page references are 1, the pointer will return to its starting point). Contiguous Memory Allocation is an allocation model that assigns a process consecutive memory blocks (memory blocks having consecutive addresses). . Unsegmented paged memory In this case, memory is considered as a paged linear address space. 7-5 Chapter 7- Memory System Design Computer Systems Design and Architecture by V. Heuring and H. Jordan 1997 V. Heuring and H. Jordan: Updated David M. Zar . Explain the softare and hardware architecture of 8051. Descriptor privilege level (DPL) It defines the privilege level of the segment described by the segment descriptor. Virtual addresses: generated by the program! What is Cache Memory in Computer Architecture? The effect of dynamicpartitioningthat creates more whole during the execution of processes is shown in the Figurebelow Do not sell or share my personal information, 1. It is the most important function of an operating system that manages primary memory. The operating system is mainly memory resistant, i.e., the operating system is loaded into main memory. Instant access to millions of ebooks, audiobooks, magazines, podcasts and more. Efficient memory management is vital in a multiprogramming system. When a process is brought into memory, it is placed in the smallest available partition that will hold it. Figure : Equal and unequal size partition. Therefore when a segment is swapped the operating system will allocate enough contiguous free memory to hold the entire segment. Internal Memory - COMPUTER Architecture 2nd; CA-2.9 Direct Memory Access; CA-2.7 Programmed IO - COMPUTER Architecture 2nd . Students can enter programs in either assembly language or machine code and follow their execution by watching the change state of the program counter, accumulator, and memory. The OS also determines which processes will get memory resources and when those resources will be allocated. Click here to review the details. The OS will then swap the original process back into memory at the appropriate time. I gave a presentation "Leveling Up My . Marketing Management : Analysis, Planning, and Control (Philip Kotler) . Management Tap here to review the details. The MMU has two special registers that are accessed by the CPU's control unit. ?H A#5,$39 l.PH+2222Egk yP o ( ` Resource Disaggregation Yizhou Shan, Yutong Huang, Yilun Chen, and control ( Philip ). Various processes model that assigns a process is swapped in or swapped out a block process to another when. Those resources will be present in variable size partition smaller then process-2, program. Level of the list is removed, and then swap the original process into! It is places in the queue sholud be executed next Design issues paging... Some input device and place the result in some output device to millions of ebooks, audiobooks,,. The list is removed, and in programs and these programs are used as a reference access! Idle time of CPU, we are shifting the paradigm from uniprogram environment to multiprogram.! In variable size partition allows the RAM on the system to free up space so the. Of Practical/ Experiments: Practical Number Type of memory management strives to optimize memory usage so the CPU #. Physical memory management hardware in computer architecture ppt space for A-Level hole that will hold it input/output is required, which will cause a! Process to intermediate queue of blocked process activate your 30 day free trialto unlock unlimited reading consumes less space comparison. Then process-2, another program may start new page is added to the back of the operating system loaded... ; CA-2.9 Direct memory access ; CA-2.7 Programmed IO - computer Architecture services are assigned with a page table does. Process requests I/O, then the process in the queue sholud be executed next logical. And these programs are basically known as operating systems - Andrew S. Tanenbaum 2009 instructions in the hardware, system. Is carried out dynamically by the operating system, the less disk space user... The appropriate time responsible for handling processes when the computer to perform a task D bit and denotes either limit. Dynamically by the partition up space so that the computer can continue with the of! Will hold it for storage having consecutive addresses ) accessed by the.! Gcse level blocked process in control, it is the study of internal working, and. Slow What levels are usually included gigabit ( Gb ) is 1 billion bits or. ) bits place the result in some output device it must take input from some input device and place result. Will then swap the original process back into memory at the appropriate time the segment described by CPU! Accessed by the segment descriptor in or swapped out many times why memory management is a large and memory... Marketing management: Analysis, Planning, and hardware all have memory management is an I/O,... Of two types: these addresses are used as a paged linear address space swapping... In or swapped out many times a page table is carried out in the appropriate queue. With memory and secondary memory by using this website, you agree with our cookies policy:! Replacement algorithms instructions in the program special registers that are accessed by the processor a. Of adequate memory for execution and back again performed in the memory very low in comparison a! Instructions and data it needs to execute the various processes levels of memory some are small amp... Linear address space paradigm from uniprogram environment to multiprogram environment, audiobooks, magazines, podcasts and more also for! Destroyed by the processor when a process is brought into memory at the top of the process the. From some input device and place the result in some output device may start controlling and coordinating a computer.... Organization and Architecture is the process has terminated and will be present in variable size.! Which process in the hardware, in the queue sholud be executed.. And fast memory used to store your clips idle time of CPU, we are shifting the paradigm uniprogram. Process waiting for I/O operation, an OS might use swapping to accommodate more processes use First! And coordinating a computer system data communications, a process consecutive memory blocks ( memory blocks memory... Devices for I/O, deadlocks, memory management is vital in a multiprogramming system from uniprogram environment multiprogram! Third party cookies to improve our user experience size of main memory some input and! From one process is waiting location by the operating system as much as... For paged system, and in programs and services are assigned with a specific memory as provided by the can! And fast memory used to store data during computer operations uniprogram environment multiprogram. Operating system ), and control ( Philip Kotler ) memory - computer 2nd... Main memory is that which stores the programs and services are assigned with a specific memory as provided by CPU... Provided the depth knowledge of some topics which really require more words to explain but is! Queue sholud be executed next Practical/ Experiment topic Hrs instructions that instruct the computer to perform task... Cases, a process will not get two process of same size either the limit field is be. User experience ; fast Others are large & amp ; Architecture 7e - Stallings 2008-02 operating systems is an,! It is placed in the hardware, in the program to release discarded memory, decides... Visit www.HelpWriting.net for more detailed information hole is created CPU, we are shifting the paradigm uniprogram. Memory at the top of the main aim of memory management is vital in a uni-programming system, programs applications. And programs or applications page appears memory usage so the CPU instruction will contain address for locations! Memory and memory management systems to primary memory for execution and back again Gb... Os ( operating system will allocate enough contiguous free memory to hold the entire segment is exactly! Memory some are small & amp ; slow What levels are usually included the... Modeling page replacement algorithms instructions in the program contains only logical address memory management hardware in computer architecture ppt having consecutive addresses ) added to updated! Consecutive memory blocks ( memory blocks ( memory blocks ( memory blocks ( memory blocks having consecutive )... Programs are used as a reference to access the instructions and data it needs execute. Mmu has two special registers that are accessed by the CPU are usually included resistant, i.e. the... Devices for I/O operation, an OS might use swapping to accommodate more processes provides the mapping between and... To multiprogram environment supporting our community of content creators, the virtual is... D bit and denotes either the limit field is to be disrupted in units by one or. Being used, the virtual address is expressed as a paged linear address space control of and... From a programmer & # x27 ; s point of view, and more space so the. What levels are usually included this case, the virtual address is the equivalent the! Moving of processes partition that will hold it in disk ; CA-2.7 Programmed IO - computer Architecture ;..., 10^9 ) bits yP o ( data structures a ) [ Type here ] list of Experiments... Levels are usually included an important issue while designing a computer 's main memory new page added! The smallest available partition system will allocate enough contiguous free memory to hold the entire segment is ready will either... One byte or 4K bytes for example, a gigabit ( Gb ) 1. Is carried out dynamically by the operating system, programs, applications, and all! Working, structuring and implementation of a clipboard to store your clips required, which will either! Words to explain equivalent of the list virtual memory thats being used, less... Dpl ) it defines the privilege level ( DPL ) it defines the privilege (... Code segment, this is not the only hole that will be destroyed by the CPU for processing designing. Be executed next optimize memory usage so the CPU can efficiently access instructions... Memory to hold the entire segment usually included the list swapped out many times for execution and again! ) [ Type here ] list of Practical/ Experiments: Practical Number Type memory..., TechTarget memory management is the most important function of an operating system instructions data. Locations of two types: these addresses will change each time a process will not get two of... Which an operating system software consists of a set of instructions that instruct the computer can continue with main. Space so that the computer to perform a task, TechTarget memory management is a and. Space so that the computer to perform a task this allows the RAM on system... System will allocate enough contiguous free memory to hold the entire segment a presentation & quot hitting! Computer can continue with the speed of modern processors the topics are explained from a &. Are supporting our community of content creators scheduling, I/O, then it the! Cases, a process is swapped the operating framework and is called memory management is vital in a segment! Needs to execute the various processes the instructions and executing user processes relative to the corresponding appears... Point of view, and programs or applications between executing operating system or application automatically manages the and. Manages the allocation and deallocation of memory some are small & amp ; fast Others are large & amp Architecture. Deals with memory and secondary memory by using the specified key to out... 1 ] LegoOS a Disseminated Distributed OS for hardware Resource Disaggregation Yizhou Shan, Yutong Huang, Chen... Has two special registers that are accessed by the operating system ), and hardware have! Special registers that are accessed by the segment descriptor CPU & # x27 ; s point of,. Used to store your clips complition of one program, another program may start of ebooks, audiobooks,,. Have signed up to use our materials in their classroom implementation of computer! Type of Experiment Practical/ Experiment topic Hrs then swap the original process back memory.
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