Swapping is the process of exchanging memory pages between main memory and secondary storage, such as a hard disk. There are three types of swapping that occur. When memory becomes full, inactive processes are swapped out to disk to free up space, and are swapped back in when needed. The first UNIX systems constantly monitored free memory and swapped out processes to disk when levels fell below a threshold. Swap space is used on Linux when RAM is full, with inactive memory pages moved to the swap file to free up space. The swap cache helps avoid race conditions when processes access pages being swapped by collecting shared pages that have been copied to swap space.
This Presentation is for Memory Management in Operating System (OS). This Presentation describes the basic need for the Memory Management in our OS and its various Techniques like Swapping, Fragmentation, Paging and Segmentation.
This document provides an overview of memory management concepts in computer systems. It discusses classification of memory types, memory addressing, memory management units, allocation techniques, swapping, fragmentation, page replacement algorithms, segmentation, hardware implementation, memory mapping, byte ordering, and common memory problems. The document contains 23 pages of content on these memory management topics.
The document discusses the structure of file systems. It explains that a file system provides mechanisms for storing and accessing files and data. It uses a layered approach, with each layer responsible for specific tasks related to file management. The logical file system contains metadata and verifies permissions and paths. It maps logical file blocks to physical disk blocks using a file organization module, which also manages free space. The basic file system then issues I/O commands to access those physical blocks via device drivers, with I/O controls handling interrupts.
In the given presentation, process overview,process management scheduling typesand some more basic concepts were explained.
Kindly refere the presentation.
Swapping is the process of exchanging memory pages between main memory and secondary storage, such as a hard disk. There are three types of swapping that occur. When memory becomes full, inactive processes are swapped out to disk to free up space, and are swapped back in when needed. The first UNIX systems constantly monitored free memory and swapped out processes to disk when levels fell below a threshold. Swap space is used on Linux when RAM is full, with inactive memory pages moved to the swap file to free up space. The swap cache helps avoid race conditions when processes access pages being swapped by collecting shared pages that have been copied to swap space.
This Presentation is for Memory Management in Operating System (OS). This Presentation describes the basic need for the Memory Management in our OS and its various Techniques like Swapping, Fragmentation, Paging and Segmentation.
This document provides an overview of memory management concepts in computer systems. It discusses classification of memory types, memory addressing, memory management units, allocation techniques, swapping, fragmentation, page replacement algorithms, segmentation, hardware implementation, memory mapping, byte ordering, and common memory problems. The document contains 23 pages of content on these memory management topics.
The document discusses the structure of file systems. It explains that a file system provides mechanisms for storing and accessing files and data. It uses a layered approach, with each layer responsible for specific tasks related to file management. The logical file system contains metadata and verifies permissions and paths. It maps logical file blocks to physical disk blocks using a file organization module, which also manages free space. The basic file system then issues I/O commands to access those physical blocks via device drivers, with I/O controls handling interrupts.
In the given presentation, process overview,process management scheduling typesand some more basic concepts were explained.
Kindly refere the presentation.
Memory management is the act of managing computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single process might be underway at any time
This document provides an overview of processes and process management in operating systems. It discusses how processes are created using fork() and how a new program can be run using exec(). The fork() system call duplicates the calling process, while exec() replaces the current process memory with a new program. The parent process id and child process id are returned and wait() is used by the parent to wait for a child process to terminate.
The document discusses different memory management strategies:
- Swapping allows processes to be swapped temporarily out of memory to disk, then back into memory for continued execution. This improves memory utilization but incurs long swap times.
- Contiguous memory allocation allocates processes into contiguous regions of physical memory using techniques like memory mapping and dynamic storage allocation with first-fit or best-fit. This can cause external and internal fragmentation over time.
- Paging permits the physical memory used by a process to be noncontiguous by dividing memory into pages and mapping virtual addresses to physical frames, allowing more efficient use of memory but requiring page tables for translation.
Memory management is the method by which an operating system handles and allocates primary memory. It tracks the status of memory locations as allocated or free, and determines how memory is distributed among competing processes. Memory can be allocated contiguously or non-contiguously. Contiguous allocation assigns consecutive blocks of memory to a process, while non-contiguous allocation allows a process's memory blocks to be scattered across different areas using techniques like paging or segmentation. Paging divides processes and memory into fixed-size pages and frames to allow non-contiguous allocation while reducing fragmentation.
The document summarizes four early memory management techniques: fixed partitions, dynamic partitions, relocatable dynamic partitions, and single-user systems. It describes best-fit and first-fit allocation schemes, the importance of deallocation, and how compaction reclaims fragmented memory to improve throughput. Special registers like the bounds and relocation registers help track memory addresses during allocation and relocation.
The document discusses fragmentation in operating systems. It defines fragmentation as when free memory becomes broken into small pieces that are not large enough to allocate to processes. There are two types of fragmentation: external fragmentation, which occurs when memory is released and the free space is broken into small pieces; and internal fragmentation, which occurs when allocated memory is larger than the requested size. Solutions to fragmentation include segmentation, paging, and memory allocation strategies like first fit, best fit, and worst fit.
The document discusses process management in operating systems. It defines a process as a program during execution, which requires resources like memory and CPU registers. The document outlines the life cycle of a process, including the different states a process can be in like ready, running, waiting, blocked. It describes process creation and termination. The process control block (PCB) contains information needed to control and monitor each process. Context switching allows the CPU to switch between processes. Scheduling determines which process enters the running state. The document lists some common process control system calls and discusses advantages and disadvantages of process management.
The document discusses various concepts related to process management in operating systems including process scheduling, CPU scheduling, and process synchronization. It defines a process as a program in execution and describes the different states a process can be in during its lifecycle. It also discusses process control blocks which maintain information about each process, and various scheduling algorithms like first come first serve, shortest job first, priority and round robin scheduling.
This document discusses threads and multithreading in operating systems. A thread is a flow of execution through a process with its own program counter, registers, and stack. Multithreading allows multiple threads within a process to run concurrently on multiple processors. There are three relationship models between user threads and kernel threads: many-to-many, many-to-one, and one-to-one. User threads are managed in userspace while kernel threads are managed by the operating system kernel. Both have advantages and disadvantages related to performance, concurrency, and complexity.
This chapter discusses file systems and their interfaces. It covers key concepts like files, directories, access methods, mounting file systems, file sharing, and protection. Directories provide structure and organization for files on a file system using tree or graph structures. File systems support operations like creating/deleting files, searching directories, and opening/closing files. They also implement features like file sharing across networks and access control using permissions.
Virtual Memory
• Copy-on-Write
• Page Replacement
• Allocation of Frames
• Thrashing
• Operating-System Examples
Background
Page Table When Some PagesAre Not in Main Memory
Steps in Handling a Page Fault
This document discusses memory management techniques used in operating systems, including:
- Base and limit registers that define the logical address space and protect memory accesses.
- Address binding from source code to executable addresses at different stages.
- The memory management unit (MMU) that maps virtual to physical addresses using base/limit registers.
- Segmentation architecture that divides memory into logical segments like code, data, stack, heap.
PowerPoint Presentation on Distributed Operating Systems,reasons for opting for distributed systems over centralized systems,types of Distributed Systems,Process Migration and its advantages.
This document discusses different memory management techniques used in operating systems. It begins by describing the basic components and functions of memory. It then explains various memory management algorithms like overlays, swapping, paging and segmentation. Overlays divide a program into instruction sets that are loaded and unloaded as needed. Swapping loads entire processes into memory for execution then writes them back to disk. Paging and segmentation are used to map logical addresses to physical addresses through page tables and segment tables respectively. The document compares advantages and limitations of these approaches.
The document discusses key concepts related to distributed file systems including:
1. Files are accessed using location transparency where the physical location is hidden from users. File names do not reveal storage locations and names do not change when locations change.
2. Remote files can be mounted to local directories, making them appear local while maintaining location independence. Caching is used to reduce network traffic by storing recently accessed data locally.
3. Fault tolerance is improved through techniques like stateless server designs, file replication across failure independent machines, and read-only replication for consistency. Scalability is achieved by adding new nodes and using decentralized control through clustering.
The document discusses several key process scheduling policies and algorithms:
1. Maximum throughput, minimize response time, and other policies aim to optimize different performance metrics like job completion time.
2. Common scheduling algorithms include first come first served (FCFS), shortest job next (SJN), priority scheduling, round robin, and multilevel queues. Each has advantages for different workload types.
3. The document also covers process synchronization challenges like deadlock and livelock that can occur when processes contend for shared resources in certain ordering. Methods to avoid or recover from such issues are important for system design.
The document discusses three common multithreading models: many-to-one, one-to-one, and many-to-many. It also describes common high-level program structures for multithreaded programs like the boss/workers model, pipeline model, up-calls, and using version stamps to keep shared information consistent.
This document discusses different approaches to memory management in operating systems. It begins by describing monoprogramming without swapping or paging, where one program uses all available memory at a time. It then describes multiprogramming using fixed memory partitions, either with separate queues for each partition or a single queue. The challenges of relocation and protection when programs are loaded at different addresses are also covered. Finally, it introduces the concepts of swapping and virtual memory for handling situations where not all active processes fit in main memory.
The Objectives of these slides are:
- To provide a detailed description of various ways of organizing memory hardware
- To discuss various memory-management techniques, including paging and segmentation
- To provide a detailed description of the Intel Pentium, which supports both pure segmentation and segmentation with paging
Memory management is the act of managing computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single process might be underway at any time
This document provides an overview of processes and process management in operating systems. It discusses how processes are created using fork() and how a new program can be run using exec(). The fork() system call duplicates the calling process, while exec() replaces the current process memory with a new program. The parent process id and child process id are returned and wait() is used by the parent to wait for a child process to terminate.
The document discusses different memory management strategies:
- Swapping allows processes to be swapped temporarily out of memory to disk, then back into memory for continued execution. This improves memory utilization but incurs long swap times.
- Contiguous memory allocation allocates processes into contiguous regions of physical memory using techniques like memory mapping and dynamic storage allocation with first-fit or best-fit. This can cause external and internal fragmentation over time.
- Paging permits the physical memory used by a process to be noncontiguous by dividing memory into pages and mapping virtual addresses to physical frames, allowing more efficient use of memory but requiring page tables for translation.
Memory management is the method by which an operating system handles and allocates primary memory. It tracks the status of memory locations as allocated or free, and determines how memory is distributed among competing processes. Memory can be allocated contiguously or non-contiguously. Contiguous allocation assigns consecutive blocks of memory to a process, while non-contiguous allocation allows a process's memory blocks to be scattered across different areas using techniques like paging or segmentation. Paging divides processes and memory into fixed-size pages and frames to allow non-contiguous allocation while reducing fragmentation.
The document summarizes four early memory management techniques: fixed partitions, dynamic partitions, relocatable dynamic partitions, and single-user systems. It describes best-fit and first-fit allocation schemes, the importance of deallocation, and how compaction reclaims fragmented memory to improve throughput. Special registers like the bounds and relocation registers help track memory addresses during allocation and relocation.
The document discusses fragmentation in operating systems. It defines fragmentation as when free memory becomes broken into small pieces that are not large enough to allocate to processes. There are two types of fragmentation: external fragmentation, which occurs when memory is released and the free space is broken into small pieces; and internal fragmentation, which occurs when allocated memory is larger than the requested size. Solutions to fragmentation include segmentation, paging, and memory allocation strategies like first fit, best fit, and worst fit.
The document discusses process management in operating systems. It defines a process as a program during execution, which requires resources like memory and CPU registers. The document outlines the life cycle of a process, including the different states a process can be in like ready, running, waiting, blocked. It describes process creation and termination. The process control block (PCB) contains information needed to control and monitor each process. Context switching allows the CPU to switch between processes. Scheduling determines which process enters the running state. The document lists some common process control system calls and discusses advantages and disadvantages of process management.
The document discusses various concepts related to process management in operating systems including process scheduling, CPU scheduling, and process synchronization. It defines a process as a program in execution and describes the different states a process can be in during its lifecycle. It also discusses process control blocks which maintain information about each process, and various scheduling algorithms like first come first serve, shortest job first, priority and round robin scheduling.
This document discusses threads and multithreading in operating systems. A thread is a flow of execution through a process with its own program counter, registers, and stack. Multithreading allows multiple threads within a process to run concurrently on multiple processors. There are three relationship models between user threads and kernel threads: many-to-many, many-to-one, and one-to-one. User threads are managed in userspace while kernel threads are managed by the operating system kernel. Both have advantages and disadvantages related to performance, concurrency, and complexity.
This chapter discusses file systems and their interfaces. It covers key concepts like files, directories, access methods, mounting file systems, file sharing, and protection. Directories provide structure and organization for files on a file system using tree or graph structures. File systems support operations like creating/deleting files, searching directories, and opening/closing files. They also implement features like file sharing across networks and access control using permissions.
Virtual Memory
• Copy-on-Write
• Page Replacement
• Allocation of Frames
• Thrashing
• Operating-System Examples
Background
Page Table When Some PagesAre Not in Main Memory
Steps in Handling a Page Fault
This document discusses memory management techniques used in operating systems, including:
- Base and limit registers that define the logical address space and protect memory accesses.
- Address binding from source code to executable addresses at different stages.
- The memory management unit (MMU) that maps virtual to physical addresses using base/limit registers.
- Segmentation architecture that divides memory into logical segments like code, data, stack, heap.
PowerPoint Presentation on Distributed Operating Systems,reasons for opting for distributed systems over centralized systems,types of Distributed Systems,Process Migration and its advantages.
This document discusses different memory management techniques used in operating systems. It begins by describing the basic components and functions of memory. It then explains various memory management algorithms like overlays, swapping, paging and segmentation. Overlays divide a program into instruction sets that are loaded and unloaded as needed. Swapping loads entire processes into memory for execution then writes them back to disk. Paging and segmentation are used to map logical addresses to physical addresses through page tables and segment tables respectively. The document compares advantages and limitations of these approaches.
The document discusses key concepts related to distributed file systems including:
1. Files are accessed using location transparency where the physical location is hidden from users. File names do not reveal storage locations and names do not change when locations change.
2. Remote files can be mounted to local directories, making them appear local while maintaining location independence. Caching is used to reduce network traffic by storing recently accessed data locally.
3. Fault tolerance is improved through techniques like stateless server designs, file replication across failure independent machines, and read-only replication for consistency. Scalability is achieved by adding new nodes and using decentralized control through clustering.
The document discusses several key process scheduling policies and algorithms:
1. Maximum throughput, minimize response time, and other policies aim to optimize different performance metrics like job completion time.
2. Common scheduling algorithms include first come first served (FCFS), shortest job next (SJN), priority scheduling, round robin, and multilevel queues. Each has advantages for different workload types.
3. The document also covers process synchronization challenges like deadlock and livelock that can occur when processes contend for shared resources in certain ordering. Methods to avoid or recover from such issues are important for system design.
The document discusses three common multithreading models: many-to-one, one-to-one, and many-to-many. It also describes common high-level program structures for multithreaded programs like the boss/workers model, pipeline model, up-calls, and using version stamps to keep shared information consistent.
This document discusses different approaches to memory management in operating systems. It begins by describing monoprogramming without swapping or paging, where one program uses all available memory at a time. It then describes multiprogramming using fixed memory partitions, either with separate queues for each partition or a single queue. The challenges of relocation and protection when programs are loaded at different addresses are also covered. Finally, it introduces the concepts of swapping and virtual memory for handling situations where not all active processes fit in main memory.
The Objectives of these slides are:
- To provide a detailed description of various ways of organizing memory hardware
- To discuss various memory-management techniques, including paging and segmentation
- To provide a detailed description of the Intel Pentium, which supports both pure segmentation and segmentation with paging
The document discusses memory management techniques used in operating systems. It covers logical versus physical address spaces and introduces paging as a memory management technique. Paging divides both main memory and disk storage into fixed-sized pages. Each process has a page table containing entries for its pages, with each entry mapping a page to a frame in main memory if present or being invalid if on disk. The CPU address is divided into a page number to index the table and an offset to access within the page.
memory managment on computer science.pptfootydigarse
Description:
This PowerPoint presentation delves into the critical realm of memory management, exploring strategies to optimize system performance and resource utilization. Beginning with an overview of memory management fundamentals, the presentation progresses to examine various memory management techniques employed in modern computing environments. Topics covered include memory allocation algorithms, memory fragmentation mitigation strategies, virtual memory concepts, and the role of caching mechanisms. Through illustrative diagrams, case studies, and real-world examples, the presentation offers insights into best practices for memory management across different computing platforms. Additionally, emerging trends and advancements in memory management technologies are explored, providing attendees with a comprehensive understanding of how to leverage memory management to enhance system efficiency, scalability, and reliability. Whether you're a seasoned IT professional, a software developer, or a student eager to expand your knowledge of memory management, this presentation offers valuable insights into the intricacies of memory optimization in contemporary computing systems.
Memory Management in Operating Systems for allVSKAMCSPSGCT
The document discusses memory management techniques used in computer systems. It describes the memory hierarchy from fast registers to slower main memory and disk. Memory management aims to efficiently allocate memory for multiple processes while providing protection, relocation, sharing and logical organization. Techniques include contiguous allocation, fixed and dynamic partitioning, paging using page tables, segmentation using segment tables, and swapping processes in and out of memory. Hardware support through relocation registers, memory management units, translation lookaside buffers and associative memory help map logical to physical addresses efficiently.
This document provides an overview of memory management techniques in operating systems. It discusses the basic requirements of memory management including relocation, protection, sharing, and logical/physical organization. It then describes different partitioning approaches like fixed, dynamic, and buddy systems. Next, it covers paging which divides memory into equal-sized pages and processes into pages, requiring page tables. Finally, it discusses segmentation which divides programs into variable-length segments addressed by segment number and offset.
This document discusses memory management and paging in operating systems. It explains that memory management allocates space for application routines and prevents interference between programs. The memory hierarchy includes main memory, cache memory, and secondary storage. Paging is a memory management technique that divides processes and main memory into equal pages. It allows processes to be non-contiguous in memory. The operating system uses page tables to map logical addresses to physical addresses stored across different pages and frames. Paging reduces external fragmentation but can cause internal fragmentation.
Evolution, Strutcture and Operations.pptxssuser000e54
The document discusses the evolution of operating systems from serial processing in the 1940s-1950s to modern distributed systems. It covers early batch processing systems and the transition to time-sharing and parallel/distributed systems. It also summarizes key aspects of operating system structure like process management, memory management, storage management, and caching techniques.
This document provides an overview of memory management techniques in operating systems, including both static and dynamic allocation approaches. It discusses fixed and variable partitioning for static allocation, as well as first-fit, next-fit, best-fit, and worst-fit algorithms for dynamic allocation. The document also covers fragmentation, base-limit registers, swapping, paging, and segmentation for virtual memory management. The key aspects of paging include using page tables to map virtual to physical addresses, allowing sharing and abstracting physical organization. Segmentation divides memory into logical segments specified by segment tables.
Storage management controls computer memory by allocating blocks to programs and freeing blocks when no longer needed. This allows multiprogramming to improve performance. Files are organized in a directory structure on storage devices like disks. The file system controls how data and programs are stored and retrieved. Common file operations include create, read, write, delete and more. Memory management techniques like paging and segmentation allow processes to execute using virtual memory larger than physical memory. Page replacement algorithms determine which memory pages to page out to disk to allocate space for new pages.
The document discusses memory management requirements and techniques. The principal responsibilities of memory management are to bring processes into memory for processor execution to ensure sufficient ready processes, and to handle the movement of information between logical and physical memory levels on behalf of the programmer. Memory can be partitioned using fixed, dynamic, or buddy system approaches. Paging and segmentation divide processes into uniform and variable sized chunks respectively and use address translation via tables to map virtual to physical addresses during relocation.
The document discusses various topics related to memory management in operating systems including swapping, contiguous memory allocation, paging, segmentation, virtual memory concepts like demand paging, page replacement, and thrashing. It provides details on page tables, segmentation hardware, logical to physical address translation, and performance aspects of demand paging. The key aspects covered are memory management techniques to overcome fragmentation and enable efficient use of limited main memory.
Operating systems use main memory management techniques like paging and segmentation to allocate memory to processes efficiently. Paging divides both logical and physical memory into fixed-size pages. It uses a page table to map logical page numbers to physical frame numbers. This allows processes to be allocated non-contiguous physical frames. A translation lookaside buffer (TLB) caches recent page translations to improve performance by avoiding slow accesses to the page table in memory. Protection bits and valid/invalid bits ensure processes only access their allocated memory regions.
Operating Systems 1 (9/12) - Memory Management ConceptsPeter Tröger
The document discusses memory management concepts in operating systems including:
- Memory is a critical resource that must be managed by the operating system to allow multiple processes to efficiently share the physical memory.
- The operating system implements virtual memory which maps process logical addresses to physical addresses to isolate processes.
- A memory management unit (MMU) hardware performs this address translation transparently.
- Memory is organized in a hierarchy from fast expensive cache/RAM to slower cheaper disk storage.
- The operating system uses paging, swapping and memory partitioning to manage this hierarchy and allocate memory to processes.
This document discusses the differences between the stack and the heap in computing memory. The stack is a temporary storage area where function variables are stored. Data is added or removed in a last-in, first-out manner. The stack has a fixed size and data is automatically deleted when a function exits. The heap is used for dynamic memory allocation and data remains until manually deleted. The stack is faster than the heap for memory allocation due to its structure. Examples are given showing how variables are allocated on the stack or heap.
Techniques for Writing Embedded Code: Memory Management, Types of Memory, Making the Most of Your RAM, Performance and Battery Life, Libraries, Debugging, Business Models: A Short History of Business Models, Space and Time, From Craft to Mass Production, The Long Tail of the Internet, Learning from History, The Business Model Canvas, Who Is the Business Model For? Models, Make Thing, Sell Thing, Subscriptions, Customisation, Be a Key Resource, Provide Infrastructure: Sensor Networks, Take a Percentage, Funding an Internet of Things Startup, Hobby Projects and Open Source, Venture Capital, Government Funding, Crowdfunding, Lean Startups.
This document discusses different approaches to memory management in computer systems. It explains that memory plays a central role, with the CPU and I/O system interacting with memory. It then describes four approaches to memory allocation and management: contiguous storage allocation, non-contiguous storage allocation, virtual storage using paging, and virtual storage using segmentation. Paging divides memory into fixed-size frames and logical memory into same-sized pages, using a page table to map logical to physical addresses. Segmentation divides a program into variable-sized segments and uses a segment table to map two-dimensional physical addresses. The most efficient approach sometimes combines paging and segmentation.
Describe about the heap memory management such as memory allocation & deallocation. Explained the Memory manager functionality and fragmentation issues.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Communicating effectively and consistently with students can help them feel at ease during their learning experience and provide the instructor with a communication trail to track the course's progress. This workshop will take you through constructing an engaging course container to facilitate effective communication.
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
Gender and Mental Health - Counselling and Family Therapy Applications and In...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
2. Introduction
• Management of main memory is critical.
• The performance of the entire system has been directly
dependent on two things:
• How much memory is available
• How it is optimization while jobs are being processed.
• This chapter introduces:
• The memory manager (RAM)
• Core memory (primary storage)
3. Introduction
• This chapter introduces:
• Four types of memory allocation schemes
• Single-user systems
• Fixed partitions
• Dynamic partitions
• Relocatable dynamic partitions
• These early memory management schemes are seldom
used by today’s OSs but are important to study because
each one introduced fundamental concepts that helped
memory management evolve.
4. Single-User Contiguous Scheme
• Commercially available in 1940s and 1950s
• Each program was loaded in its entirety into memory and
allocated as much contiguous memory space allocated as
it needed.
• If the program was too large and didn’t fit the
available memory space, it couldn’t be executed,
• Although early computers were physically large, they had
very little memory.
• Computers have only a finite amount of memory.
5. Single-User Contiguous Scheme
• If a program doesn’t fit, then either the size of the main
memory must be increased or the program must be
modified.
• Making it smaller
• Using methods that allow program segments
(partitions made to the program) to be overlaid.
• Transfer segments of a program from secondary
storage into main memory for execution
• Two or more segments take turns occupying the
same memory locations.
6. Memory Management
Concurrency
• A program cannot process data it does not have.
• A program spends more time waiting for I/O than
processing data.
7. Single-User Contiguous Scheme
• The amount of work performed by the Memory Manager is
minimal.
• Only two hardware items are needed:
• A register to store the base address
• An accumulator to keep track of the size of the program
as it’s being read into memory.
• Once the program is entirely loaded into memory, it
remains there until execution is complete, either through
normal termination or by intervention of the OS.
8. Single-User Contiguous Scheme
(cont'd.)
• Disadvantages
• There is no support for multiprogramming or networking
• It can handle only one job at a time.
• This configuration was first used in research institutions
but proved unacceptable for the business community.
• It was not cost effective to spend almost $200,000 for
equipment that could be used by only one person ay a
time.
9. Fixed Partitions
• The first attempt to follow multiprogramming used fixed
partitions (static partitions) within main memory.
• One partition for each job.
• The size of each partition was designated when the system
was powered on.
• Each partition could only be reconfigured when the
system was shut down.
• Once the system was in operation, the partition sizes
remained static.
10. Fixed Partitions
• Introduced protection of the job’s memory space
• Once a partition was assigned to a job, no other job could be allowed
to enter its boundaries, either accidentally or intentionally.
• Not a problem in single-user contiguous allocation schemes.
• Fixed Partitions is more flexible than the Single-User scheme
because it allows several programs to be in memory at the
same time.
• Fixed Partitions still requires that the entire program be
stored contiguously and in memory from the beginning to the
end of its execution.
11. Fixed Partitions
• In order to allocate memory spaces to jobs, the OS’s Memory
Manager must keep a table which shows:
• Each memory partition size
• Its address
• Its access restrictions
• Its current status (free or busy)
• As each job terminates, the status of its memory partition is
changed from busy to free so an incoming job can be assigned
to that partition.
12. Fixed Partitions (cont'd.)
• Disadvantages
• The Fixed Partition scheme works well if all the jobs run on
the system are of the same size or if the sizes are known
ahead of time and don’t vary between reconfiguration.
• If the partition sizes are too small:
• larger jobs will be rejected if they’re too big to fit into the
largest partition.
• Large jobs will wait if the large partitions are busy.
• Large jobs may have a longer turnaround time as they
wait for free partitions of sufficient size or may never run.
13. Fixed Partitions (cont'd.)
• Disadvantages
• If the partition sizes are too big, memory is wasted.
• If a job does not occupy the entire partition, the unused
memory in the partition will remain idle.
• It can’t be given to another job because each partition is
allocated to only one job at a time.
• Partial usage of fixed partitions and the coinciding creation
of unused spaces within the partition is called internal
fragmentation and is a major drawback to the fixed
partition memory allocation scheme.
14. Dynamic Partitions
• With Dynamic Partitions available memory is still kept in
contiguous blocks but jobs are given only as much memory as
they request when they are loaded for processing.
• A dynamic partition scheme fully utilizes memory when the
first jobs are loaded.
• As new jobs enter the system that are not the same size as
those that just vacated memory, they are fit into the available
spaces on a priority basis.
• First Come – First Serve priority
15. Dynamic Partitions
• The subsequent allocation of memory creates fragments
of free memory between blocks of allocated memory.
• External fragmentation
• Lets memory go to waste
17. Best-FitVersus First-Fit Allocation
• For both fixed and dynamic memory allocation schemes, the
OS must keep lists of each memory location noting which are
free and which are busy.
• As new jobs come into the system, the free partitions must be
allocated.
• These partitions may be allocated on the basis of:
• First-fit memory allocation:
• First partition fitting the requirements
• Best-fit memory allocation:
• Smallest partition fitting the requirements
• Least wasted space
20. Best-FitVersus First-Fit Allocation
(cont'd.)
• Algorithm for first-fit
• Assumes memory manager keeps two lists
• One for free memory blocks
• One for busy memory blocks
• The operation consists of a simple loop that compares
the size of each job to the size of each memory block until
a block is found that is large enough to fit the job.
• The job is stored into that block of memory and the
Memory Manager moves out of the loop to fetch the next
job from the entry queue
21. Best-FitVersus First-Fit Allocation
(cont'd.)
• Algorithm for first-fit (cont'd.):
• If the entire list is searched in vain, then the job is
placed into a waiting queue.
• The Memory Manager then fetches the next job and
repeats the process.
23. Best-FitVersus First-Fit Allocation
(cont'd.)
• Algorithm for best-fit
• The goal is to find the smallest memory block into
which the job will fit
• The entire table must be searched before the
allocation can be made because the memory blocks
are physically stored in sequence according to their
location in memory.
25. Best-FitVersus First-Fit Allocation
(cont'd.)
• Hypothetical allocation schemes
• Next-fit:
• Starts searching from last allocated block, for next
available block when a new job arrives
• Worst-fit:
• Allocates largest free available block to new job
• Opposite of best-fit
• Good way to explore theory of memory allocation
• Not best choice for an actual system
26. Deallocation
• There eventually comes a time when memory space must
be released or deallocated.
• For a fixed-partition system:
• When the job is completed, the Memory Manager
resets the status of the memory block where the job
was stored to “free”.
• Any code may be used.
• Example code: binary values with zero indicating
free and one indicating busy.
27. Deallocation (cont'd.)
• For dynamic-partition system:
• A more complexAlgorithm is used because the algorithm
tries to combine free areas of memory whenever possible.
• The system must be prepared for three alternative
solutions:
• Case 1:When the block to be deallocated is adjacent
to another free block
• Case 2:When the block to be deallocated is between
two free blocks
• Case 3:When the block to be deallocated is isolated
from other free blocks