Segmentation topic is presented in a most easy way.
Segmentation is a user view of memory in Operating System. Segmentation is one of the most common ways to achieve memory protection. In a computer system using segmentation, an instruction operand that refers to a memory location includes a value that identifies a segment and an offset within that segment.
This document discusses segmentation in operating systems. Segmentation divides memory into variable-sized segments rather than fixed pages. Each process is divided into segments like the main program, functions, variables, etc. There are two types of segmentation: virtual memory segmentation which loads segments non-contiguously and simple segmentation which loads all segments together at once but non-contiguously in memory. Segmentation uses a segment table to map the two-part logical address to the single physical address through looking up the segment base address.
This document summarizes and compares paging and segmentation, two common memory management techniques. Paging divides physical memory into fixed-size frames and logical memory into same-sized pages. It maps pages to frames using a page table. Segmentation divides logical memory into variable-sized segments and uses a segment table to map segment numbers to physical addresses. Paging avoids external fragmentation but can cause internal fragmentation, while segmentation avoids internal fragmentation but can cause external fragmentation. Both approaches separate logical and physical address spaces but represent different models of how a process views memory.
The document discusses the concept of virtual memory. Virtual memory allows a program to access more memory than what is physically available in RAM by storing unused portions of the program on disk. When a program requests data that is not currently in RAM, it triggers a page fault that causes the needed page to be swapped from disk into RAM. This allows the illusion of more memory than physically available through swapping pages between RAM and disk as needed by the program during execution.
Digital Signature, Electronic Signature, How digital signature works, Confidentiality of digital signature, Authenticity of digital signature, Integrity of digital signature, standard of digital signature, Algorithm of digital signature, Mathematical base of digital signature, parameters of digital signature, key computation of digital signature, key generation of digital signature, verification of of digital signature
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.
The document is a chapter from a textbook on data mining written by Akannsha A. Totewar, a professor at YCCE in Nagpur, India. It provides an introduction to data mining, including definitions of data mining, the motivation and evolution of the field, common data mining tasks, and major issues in data mining such as methodology, performance, and privacy.
This presentation describes about the various memory allocation methods like first fit, best fit and worst fit in memory management and also about fragmentation problem and solution for the problem.
Paging and Segmentation in Operating SystemRaj Mohan
The document discusses different types of memory used in computers including physical memory, logical memory, and virtual memory. It describes how virtual memory uses paging and segmentation techniques to allow programs to access more memory than is physically available. Paging divides memory into fixed-size pages that can be swapped between RAM and secondary storage, while segmentation divides memory into variable-length, protected segments. The combination of paging and segmentation provides memory protection and efficient use of available RAM.
Paging is a memory management technique that allows a process to be allocated physical memory wherever it is available. It divides both physical memory and logical memory into fixed-sized blocks called frames and pages respectively. When a process runs, its pages are loaded into available free frames. A page table maps the logical addresses to physical frames and is used to translate logical addresses to physical addresses during execution. Address translation uses the page number as an index into the page table to find the physical frame number.
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
The document discusses virtual memory, including its needs, importance, advantages, and disadvantages. Virtual memory allows a computer to use more memory for programs than is physically installed by storing unused portions on disk. This allows processes to exceed physical memory limits. Page replacement algorithms like FIFO, LRU, and OPT are used to determine which pages to swap in and out between memory and disk.
Bus structure in Computer Organization.pdfmvpk14486
Buses connect components in a computer system and allow for the transfer of data and control signals. There are three main types of buses: the address bus carries memory and I/O addresses, the data bus carries data and instructions, and the control bus carries signals that determine read, write, I/O, and synchronization operations. A system bus combines the functions of these three buses to connect major computer components like the processor, memory, and I/O devices.
Knowledge representation techniques face several issues including representing important attributes of objects, relationships between attributes, choosing the level of detail in representations, depicting sets of multiple objects, and determining appropriate structures as needed.
Dbms Notes Lecture 9 : Specialization, Generalization and AggregationBIT Durg
This document discusses key concepts in the Extended Entity Relationship (EER) model, including specialization, generalization, attribute inheritance, and aggregation. Specialization involves dividing a higher-level entity set into lower-level subsets, while generalization groups multiple lower-level entity sets into a single higher-level set based on common attributes. Attribute inheritance allows attributes to be passed from higher to lower levels. Aggregation models relationships between relationships by treating them as higher-level entities. The document provides examples and discusses constraints like disjointness and completeness that can be applied.
The document discusses code optimization techniques in compilers. It covers the following key points:
1. Code optimization aims to improve code performance by replacing high-level constructs with more efficient low-level code while preserving program semantics. It occurs at various compiler phases like source code, intermediate code, and target code.
2. Common optimization techniques include constant folding, propagation, algebraic simplification, strength reduction, copy propagation, and dead code elimination. Control and data flow analysis are required to perform many optimizations.
3. Optimizations can be local within basic blocks, global across blocks, or inter-procedural across procedures. Representations like flow graphs, basic blocks, and DAGs are used to apply optimizations at
Gives an overview about Process, PCB, Process States, Process Operations, Scheduling, Schedulers, Interprocess communication, shared memory and message passing systems
The document discusses code generation in compilers. It describes the main tasks of the code generator as instruction selection, register allocation and assignment, and instruction ordering. It then discusses various issues in designing a code generator such as the input and output formats, memory management, different instruction selection and register allocation approaches, and choice of evaluation order. The target machine used is a hypothetical machine with general purpose registers, different addressing modes, and fixed instruction costs. Examples of instruction selection and utilization of addressing modes are provided.
This document discusses the evolution of the object model in programming. It describes how programming languages have evolved from procedural to object-oriented over several generations, with each generation incorporating new features like data abstraction, modularity, and object-oriented concepts. The core elements of the object model are explained as abstraction, encapsulation, hierarchy, and modularity. Minor elements like typing, concurrency, and persistence are also discussed. Examples are given throughout to illustrate object-oriented concepts.
The document discusses addressing modes in computers. It defines addressing modes as the different ways of specifying the location of an operand in an instruction. It describes 10 common addressing modes including implied, immediate, register, register indirect, auto increment/decrement, direct, indirect, relative, indexed, and base register addressing modes. It provides examples of instructions for each addressing mode and explains how the effective address is calculated. Addressing modes allow for versatility in programming through features like pointers, loop counters, data indexing, and program relocation while reducing the number of bits needed in instruction addresses.
The document discusses run-time environments and how compilers support program execution through run-time environments. It covers:
1) The compiler cooperates with the OS and system software through a run-time environment to implement language abstractions during execution.
2) The run-time environment handles storage layout/allocation, variable access, procedure linkage, parameter passing and interfacing with the OS.
3) Memory is typically divided into code, static storage, heap and stack areas, with the stack and heap growing towards opposite ends of memory dynamically during execution.
Register transfer language is used to describe micro-operation transfers between registers. It represents the sequence of micro-operations performed on binary information stored in registers and the control that initiates the sequences. A register is a group of flip-flops that store binary information. Information can be transferred between registers using replacement operators and control functions. Common bus systems using multiplexers or three-state buffers allow efficient information transfer between multiple registers by selecting one register at a time to connect to the shared bus lines. Memory transfers are represented by specifying the memory word selected by the address in a register and the data register involved in the transfer.
An instruction code consists of an operation code and operand(s) that specify the operation to perform and data to use. Operation codes are binary codes that define operations like addition, subtraction, etc. Early computers stored programs and data in separate memory sections and used a single accumulator register. Modern computers have multiple registers for temporary storage and performing operations faster than using only memory. Computer instructions encode an operation code and operand fields to specify the basic operations to perform on data stored in registers or memory.
This document discusses recursive descent parsing, which is a top-down parsing method that uses a set of recursive procedures to analyze the syntax of a program. Each nonterminal in a grammar is associated with a procedure. It attempts to construct a parse tree starting from the root node and creating child nodes in a preorder traversal. Recursive descent parsing can involve backtracking if the initial parsing path fails. An example grammar and parsing procedures using backtracking are provided to illustrate the technique.
This document discusses different approaches to implementing scope rules in programming languages. It begins by defining lexical/static scope and dynamic scope. It then discusses how block structure and nested procedures can be implemented using stacks and access links. Specifically, it describes how storage is allocated for local and non-local variables under lexical and dynamic scope models. The key implementation techniques discussed are stacks, access links, displays, deep access, and shallow access.
This document discusses dynamic memory allocation in C. It explains that dynamic allocation allows memory to be allocated at runtime, unlike static allocation which requires defining memory sizes at compile time. The key functions covered are malloc() for allocating memory blocks, calloc() for arrays and structures, realloc() for resizing allocated blocks, and free() for releasing used memory to avoid memory leaks. Examples are provided to demonstrate how each function is used.
- Paging is a memory management technique that divides logical memory into fixed-size pages and physical memory into frames. When a process is executed, its pages are loaded into any available frames. This allows physical memory to be non-contiguous while avoiding external fragmentation.
- Address translation uses a page table containing the frame number for each process page. A logical address is divided into a page number, which indexes the page table, and a page offset, which combined with the frame base address gives the physical memory location.
- Segmentation divides a process into variable-sized segments, each with a base and limit defined in a segment table. A logical address has a segment number and offset, with the offset added to the base
Paging and segmentation are methods of non-contiguous memory allocation in operating systems. Paging divides both main memory and secondary storage into equal fixed-size pages. Each process is divided into pages the size of the page frame. Segmentation divides processes into variable-sized segments stored in secondary storage. The segment table maps logical to physical addresses by storing the base address and limit of each segment. Both methods allow for more efficient memory usage but paging has less overhead while segmentation avoids internal fragmentation.
This presentation describes about the various memory allocation methods like first fit, best fit and worst fit in memory management and also about fragmentation problem and solution for the problem.
Paging and Segmentation in Operating SystemRaj Mohan
The document discusses different types of memory used in computers including physical memory, logical memory, and virtual memory. It describes how virtual memory uses paging and segmentation techniques to allow programs to access more memory than is physically available. Paging divides memory into fixed-size pages that can be swapped between RAM and secondary storage, while segmentation divides memory into variable-length, protected segments. The combination of paging and segmentation provides memory protection and efficient use of available RAM.
Paging is a memory management technique that allows a process to be allocated physical memory wherever it is available. It divides both physical memory and logical memory into fixed-sized blocks called frames and pages respectively. When a process runs, its pages are loaded into available free frames. A page table maps the logical addresses to physical frames and is used to translate logical addresses to physical addresses during execution. Address translation uses the page number as an index into the page table to find the physical frame number.
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
The document discusses virtual memory, including its needs, importance, advantages, and disadvantages. Virtual memory allows a computer to use more memory for programs than is physically installed by storing unused portions on disk. This allows processes to exceed physical memory limits. Page replacement algorithms like FIFO, LRU, and OPT are used to determine which pages to swap in and out between memory and disk.
Bus structure in Computer Organization.pdfmvpk14486
Buses connect components in a computer system and allow for the transfer of data and control signals. There are three main types of buses: the address bus carries memory and I/O addresses, the data bus carries data and instructions, and the control bus carries signals that determine read, write, I/O, and synchronization operations. A system bus combines the functions of these three buses to connect major computer components like the processor, memory, and I/O devices.
Knowledge representation techniques face several issues including representing important attributes of objects, relationships between attributes, choosing the level of detail in representations, depicting sets of multiple objects, and determining appropriate structures as needed.
Dbms Notes Lecture 9 : Specialization, Generalization and AggregationBIT Durg
This document discusses key concepts in the Extended Entity Relationship (EER) model, including specialization, generalization, attribute inheritance, and aggregation. Specialization involves dividing a higher-level entity set into lower-level subsets, while generalization groups multiple lower-level entity sets into a single higher-level set based on common attributes. Attribute inheritance allows attributes to be passed from higher to lower levels. Aggregation models relationships between relationships by treating them as higher-level entities. The document provides examples and discusses constraints like disjointness and completeness that can be applied.
The document discusses code optimization techniques in compilers. It covers the following key points:
1. Code optimization aims to improve code performance by replacing high-level constructs with more efficient low-level code while preserving program semantics. It occurs at various compiler phases like source code, intermediate code, and target code.
2. Common optimization techniques include constant folding, propagation, algebraic simplification, strength reduction, copy propagation, and dead code elimination. Control and data flow analysis are required to perform many optimizations.
3. Optimizations can be local within basic blocks, global across blocks, or inter-procedural across procedures. Representations like flow graphs, basic blocks, and DAGs are used to apply optimizations at
Gives an overview about Process, PCB, Process States, Process Operations, Scheduling, Schedulers, Interprocess communication, shared memory and message passing systems
The document discusses code generation in compilers. It describes the main tasks of the code generator as instruction selection, register allocation and assignment, and instruction ordering. It then discusses various issues in designing a code generator such as the input and output formats, memory management, different instruction selection and register allocation approaches, and choice of evaluation order. The target machine used is a hypothetical machine with general purpose registers, different addressing modes, and fixed instruction costs. Examples of instruction selection and utilization of addressing modes are provided.
This document discusses the evolution of the object model in programming. It describes how programming languages have evolved from procedural to object-oriented over several generations, with each generation incorporating new features like data abstraction, modularity, and object-oriented concepts. The core elements of the object model are explained as abstraction, encapsulation, hierarchy, and modularity. Minor elements like typing, concurrency, and persistence are also discussed. Examples are given throughout to illustrate object-oriented concepts.
The document discusses addressing modes in computers. It defines addressing modes as the different ways of specifying the location of an operand in an instruction. It describes 10 common addressing modes including implied, immediate, register, register indirect, auto increment/decrement, direct, indirect, relative, indexed, and base register addressing modes. It provides examples of instructions for each addressing mode and explains how the effective address is calculated. Addressing modes allow for versatility in programming through features like pointers, loop counters, data indexing, and program relocation while reducing the number of bits needed in instruction addresses.
The document discusses run-time environments and how compilers support program execution through run-time environments. It covers:
1) The compiler cooperates with the OS and system software through a run-time environment to implement language abstractions during execution.
2) The run-time environment handles storage layout/allocation, variable access, procedure linkage, parameter passing and interfacing with the OS.
3) Memory is typically divided into code, static storage, heap and stack areas, with the stack and heap growing towards opposite ends of memory dynamically during execution.
Register transfer language is used to describe micro-operation transfers between registers. It represents the sequence of micro-operations performed on binary information stored in registers and the control that initiates the sequences. A register is a group of flip-flops that store binary information. Information can be transferred between registers using replacement operators and control functions. Common bus systems using multiplexers or three-state buffers allow efficient information transfer between multiple registers by selecting one register at a time to connect to the shared bus lines. Memory transfers are represented by specifying the memory word selected by the address in a register and the data register involved in the transfer.
An instruction code consists of an operation code and operand(s) that specify the operation to perform and data to use. Operation codes are binary codes that define operations like addition, subtraction, etc. Early computers stored programs and data in separate memory sections and used a single accumulator register. Modern computers have multiple registers for temporary storage and performing operations faster than using only memory. Computer instructions encode an operation code and operand fields to specify the basic operations to perform on data stored in registers or memory.
This document discusses recursive descent parsing, which is a top-down parsing method that uses a set of recursive procedures to analyze the syntax of a program. Each nonterminal in a grammar is associated with a procedure. It attempts to construct a parse tree starting from the root node and creating child nodes in a preorder traversal. Recursive descent parsing can involve backtracking if the initial parsing path fails. An example grammar and parsing procedures using backtracking are provided to illustrate the technique.
This document discusses different approaches to implementing scope rules in programming languages. It begins by defining lexical/static scope and dynamic scope. It then discusses how block structure and nested procedures can be implemented using stacks and access links. Specifically, it describes how storage is allocated for local and non-local variables under lexical and dynamic scope models. The key implementation techniques discussed are stacks, access links, displays, deep access, and shallow access.
This document discusses dynamic memory allocation in C. It explains that dynamic allocation allows memory to be allocated at runtime, unlike static allocation which requires defining memory sizes at compile time. The key functions covered are malloc() for allocating memory blocks, calloc() for arrays and structures, realloc() for resizing allocated blocks, and free() for releasing used memory to avoid memory leaks. Examples are provided to demonstrate how each function is used.
- Paging is a memory management technique that divides logical memory into fixed-size pages and physical memory into frames. When a process is executed, its pages are loaded into any available frames. This allows physical memory to be non-contiguous while avoiding external fragmentation.
- Address translation uses a page table containing the frame number for each process page. A logical address is divided into a page number, which indexes the page table, and a page offset, which combined with the frame base address gives the physical memory location.
- Segmentation divides a process into variable-sized segments, each with a base and limit defined in a segment table. A logical address has a segment number and offset, with the offset added to the base
Paging and segmentation are methods of non-contiguous memory allocation in operating systems. Paging divides both main memory and secondary storage into equal fixed-size pages. Each process is divided into pages the size of the page frame. Segmentation divides processes into variable-sized segments stored in secondary storage. The segment table maps logical to physical addresses by storing the base address and limit of each segment. Both methods allow for more efficient memory usage but paging has less overhead while segmentation avoids internal fragmentation.
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.
Memory management techniques involve paging and segmentation. Paging divides memory into fixed-size blocks called frames and logical memory into same-sized blocks called pages. Segmentation divides memory into variable-sized blocks called segments. Paging uses a page table to map logical to physical addresses while segmentation uses a segment table containing the base and limit of each segment. Both techniques allocate and track memory to optimize performance but paging causes internal fragmentation while segmentation causes external fragmentation.
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.
Main memory must support both OS and user processes
Limited resource, must allocate efficiently
Contiguous allocation is one early method
Main memory usually into two partitions:
Resident operating system, usually held in low memory with interrupt vector
User processes then held in high memory
Each process contained in single contiguous section of memory
Memory Management in Operating Systems ppt.pptxbhaimodel20
Memory Management in an operating system is the subsystem responsible for controlling and coordinating computer memory, assigning portions to processes when they need it, and freeing it for reuse when they’re done. Its goals are to maximize utilization, provide protection and isolation, and support efficient execution.
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1. Key Responsibilities
Allocation & Deallocation
Assign memory regions to processes on load or request.
Reclaim memory on process termination or via explicit free calls.
Protection & Isolation
Prevent one process from accessing another’s memory.
Enforce read/write/execute permissions via hardware (MMU).
Sharing & Communication
Map shared libraries or IPC buffers into multiple address spaces.
Support copy‑on‑write to efficiently share pages until modified.
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2. Allocation Strategies
Contiguous Allocation
Fixed partitions: Memory divided into static regions; simple but inflexible.
Dynamic partitions: Fit variable‑sized segments via first‑fit, best‑fit, or worst‑fit; suffers external fragmentation.
Non‑Contiguous Allocation
Paging: Breaks memory into equal‑sized frames (physical) and pages (logical). Page tables map pages→frames, eliminating external fragmentation.
Segmentation: Divides programs into logical segments (code, data, stack) of varying length; supports protection per segment but can fragment.
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3. Virtual Memory
Concept: Gives each process the illusion of a large, contiguous address space, even if physical RAM is smaller.
Demand Paging: Pages are loaded into RAM only when first accessed (“page fault”).
Swapping: Entire processes or individual pages can be moved to disk (swap space) when memory is scarce.
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4. Page Replacement Algorithms
When RAM is full and a new page is needed, the OS must evict an existing page:
Optimal (Belady’s): Replace the page not needed for the longest future time (theoretical).
Least Recently Used (LRU): Evict the page unused for the longest past time.
First‑In, First‑Out (FIFO): Evict the oldest loaded page.
Clock (Second‑Chance): A circular buffer giving pages a “second chance” before eviction.
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5. Fragmentation & Compaction
External Fragmentation: Free memory is split into small blocks; can be mitigated by compaction (shifting processes), though costly.
Internal Fragmentation: Occurs when fixed‑size blocks (pages) waste space if a process doesn’t fill the last page completely.
---
6. Hardware Support
Memory Management Unit (MMU): Translates virtual addresses to physical addresses using page tables.
Translation Lookaside Buffer (TLB): A small, fast cache of recent virtual‑to‑physical translations to speed up address translation.
---
7. Advanced Techniques
Hierarchical & Inverted Page Tables: Reduce memory overhead for page tables in large address spaces.
Segmented‑Paging: Combines segmentation’s logical view with paging’s fixed‑size blocks.
Huge Pages: Use larger page sizes (e.g., 2 MiB) to reduce TLB misses for big memo
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.
Main memory is used to store programs and data for the CPU to access directly. Paging is a memory management technique that divides main memory into fixed-sized blocks called frames and divides logical memory into same-sized blocks called pages. The page table maps logical page numbers to physical frame numbers, with translation lookaside buffers caching these mappings to improve performance. Protection bits in page table entries enforce access permissions on individual pages.
This document discusses memory management techniques in operating systems. It defines memory management as the functionality that handles primary memory and moves processes between main memory and disk. It describes process address spaces and different types of addresses. It also covers static vs dynamic loading and linking, swapping, memory allocation, fragmentation, paging, segmentation, and address translation. Paging breaks processes into fixed-size blocks called pages, while segmentation divides processes into variable-length segments. The operating system uses techniques like page mapping tables, segment maps, and memory compaction to manage memory.
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 memory management techniques used by operating systems. It explains that memory management involves allocating and swapping blocks of data between main memory and secondary storage due to the slow speed of memory I/O compared to CPUs. Key requirements for memory management are relocation, protection, and sharing of memory. Early techniques like fixed and dynamic partitioning had limitations that were addressed by paging and segmentation which partition memory into small fixed-size chunks. Virtual memory management allows processes to be larger than physical memory by swapping pages or segments between main and secondary storage on demand.
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.
この資料は、Roy FieldingのREST論文(第5章)を振り返り、現代Webで誤解されがちなRESTの本質を解説しています。特に、ハイパーメディア制御やアプリケーション状態の管理に関する重要なポイントをわかりやすく紹介しています。
This presentation revisits Chapter 5 of Roy Fielding's PhD dissertation on REST, clarifying concepts that are often misunderstood in modern web design—such as hypermedia controls within representations and the role of hypermedia in managing application state.
Efficient Algorithms for Isogeny Computation on Hyperelliptic Curves: Their A...IJCNCJournal
We present efficient algorithms for computing isogenies between hyperelliptic curves, leveraging higher genus curves to enhance cryptographic protocols in the post-quantum context. Our algorithms reduce the computational complexity of isogeny computations from O(g4) to O(g3) operations for genus 2 curves, achieving significant efficiency gains over traditional elliptic curve methods. Detailed pseudocode and comprehensive complexity analyses demonstrate these improvements both theoretically and empirically. Additionally, we provide a thorough security analysis, including proofs of resistance to quantum attacks such as Shor's and Grover's algorithms. Our findings establish hyperelliptic isogeny-based cryptography as a promising candidate for secure and efficient post-quantum cryptographic systems.
Welcome to the May 2025 edition of WIPAC Monthly celebrating the 14th anniversary of the WIPAC Group and WIPAC monthly.
In this edition along with the usual news from around the industry we have three great articles for your contemplation
Firstly from Michael Dooley we have a feature article about ammonia ion selective electrodes and their online applications
Secondly we have an article from myself which highlights the increasing amount of wastewater monitoring and asks "what is the overall" strategy or are we installing monitoring for the sake of monitoring
Lastly we have an article on data as a service for resilient utility operations and how it can be used effectively.
Dear SICPA Team,
Please find attached a document outlining my professional background and experience.
I remain at your disposal should you have any questions or require further information.
Best regards,
Fabien Keller
Several studies have established that strength development in concrete is not only determined by the water/binder ratio, but it is also affected by the presence of other ingredients. With the increase in the number of concrete ingredients from the conventional four materials by addition of various types of admixtures (agricultural wastes, chemical, mineral and biological) to achieve a desired property, modelling its behavior has become more complex and challenging. Presented in this work is the possibility of adopting the Gene Expression Programming (GEP) algorithm to predict the compressive strength of concrete admixed with Ground Granulated Blast Furnace Slag (GGBFS) as Supplementary Cementitious Materials (SCMs). A set of data with satisfactory experimental results were obtained from literatures for the study. Result from the GEP algorithm was compared with that from stepwise regression analysis in order to appreciate the accuracy of GEP algorithm as compared to other data analysis program. With R-Square value and MSE of -0.94 and 5.15 respectively, The GEP algorithm proves to be more accurate in the modelling of concrete compressive strength.
How to Buy Snapchat Account A Step-by-Step Guide.pdfjamedlimmk
Scaling Growth with Multiple Snapchat Accounts: Strategies That Work
Operating multiple Snapchat accounts isn’t just a matter of logging in and out—it’s about crafting a scalable content strategy. Businesses and influencers who master this can turn Snapchat into a lead generation engine.
Key strategies include:
Content Calendars for Each Account – Plan distinct content buckets and themes per account to avoid duplication and maintain variety.
Geo-Based Content Segmentation – Use location-specific filters and cultural trends to speak directly to a region's audience.
Audience Mapping – Tailor messaging for niche segments: Gen Z, urban youth, gamers, shoppers, etc.
Metrics-Driven Storytelling – Use Snapchat Insights to monitor what type of content performs best per account.
Each account should have a unique identity but tie back to a central brand voice. This balance is crucial for brand consistency while leveraging the platform’s creative freedoms.
How Agencies and Creators Handle Bulk Snapchat Accounts
Digital agencies and creator networks often manage dozens—sometimes hundreds—of Snapchat accounts. The infrastructure to support this requires:
Dedicated teams for each cluster of accounts
Cloud-based mobile device management (MDM) systems
Permission-based account access for role clarity
Workflow automation tools (Slack, Trello, Notion) for content coordination
This is especially useful in verticals such as music promotion, event marketing, lifestyle brands, and political outreach, where each campaign needs targeted messaging from different handles.
The Legality and Risk Profile of Bulk Account Operations
If your aim is to operate or acquire multiple Snapchat accounts, understand the risk thresholds:
Personal Use (Low Risk) – One or two accounts for personal and creative projects
Business Use (Medium Risk) – Accounts with aligned goals, managed ethically
Automated Bulk Use (High Risk) – Accounts created en masse or used via bots are flagged quickly
Snapchat uses advanced machine learning detection for unusual behavior, including:
Fast switching between accounts from the same IP
Identical Snap stories across accounts
Rapid follower accumulation
Use of unverified devices or outdated OS versions
To stay compliant, use manual operations, vary behavior, and avoid gray-market account providers.
Smart Monetization Through Multi-Account Snapchat Strategies
With a multi-account setup, you can open doors to diversified monetization:
Affiliate Marketing – Niche accounts promoting targeted offers
Sponsored Content – Brands paying for story placement across multiple profiles
Product Launch Funnels – Segment users by interest and lead them to specific landing pages
Influencer Takeovers – Hosting creators across multiple themed accounts for event buzz
This turns your Snapchat network into a ROI-driven asset instead of a time sink.
Conclusion: Build an Ecosystem, Not Just Accounts
When approached correctly, multiple Snapchat accounts bec
Jacob Murphy Australia - Excels In Optimizing Software ApplicationsJacob Murphy Australia
In the world of technology, Jacob Murphy Australia stands out as a Junior Software Engineer with a passion for innovation. Holding a Bachelor of Science in Computer Science from Columbia University, Jacob's forte lies in software engineering and object-oriented programming. As a Freelance Software Engineer, he excels in optimizing software applications to deliver exceptional user experiences and operational efficiency. Jacob thrives in collaborative environments, actively engaging in design and code reviews to ensure top-notch solutions. With a diverse skill set encompassing Java, C++, Python, and Agile methodologies, Jacob is poised to be a valuable asset to any software development team.
This slide deck presents a detailed overview of the 2025 survey paper titled “A Survey of Personalized Large Language Models” by Liu et al. It explores how foundation models like GPT and LLaMA can be personalized to better reflect user-specific needs, preferences, and behaviors.
The presentation is structured around a 3-level taxonomy introduced in the paper:
Input-Level Personalization (e.g., user-profile prompting, memory retrieval)
Model-Level Personalization (e.g., LoRA, PEFT, adapters)
Objective-Level Personalization (e.g., RLHF, preference alignment)
an insightful lecture on "Loads on Structure," where we delve into the fundamental concepts and principles of load analysis in structural engineering. This presentation covers various types of loads, including dead loads, live loads, as well as their impact on building design and safety. Whether you are a student, educator, or professional in the field, this lecture will enhance your understanding of ensuring stability. Explore real-world examples and best practices that are essential for effective engineering solutions.
A lecture by Eng. Wael Almakinachi, M.Sc.
Slide share PPT of NOx control technologies.pptxvvsasane
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Presentation on Segmentation
1. What is segmentation
Segmentation is a technique to break
memory into logical pieces where each
piece represents a group of related
information.
2. Why is Segmentation used?
• Segmentation is one of the most common ways to achieve memory
protection
• Because internal fragmentation of pages takes place ,the user’s view of
memory is lost
• The user will view the memory as a combination of segments
• In this type, memory address used are not
contiguous.
• Each memory segment is associated with specific length and set of
permission
• When a process tries to access the memory it is first checked to see
whether it has the required permission to access the particular memory
segment by the particular memory
3. Segmentation
• Process are allocated with
segments
• Segment that the process
needs like
heap,stack,code,data are
divided into segments
• Segments make the
process more organized
• Logical view- multiple
separate segments
• Typical- code,data,stack
• Others-memory sharing etc
5. Segmentation Architecture
• Each segment has
contiguous memory
• Logical address consists of
a two tuple: <segment-
number, offset>,
• Segment table – maps
two-dimensional physical
addresses; each table
entry has:
• 1. base – contains the
starting physical address
where the segments
reside in memory.
• 2. limit – specifies the
length of the segment.
7. Segmentation Hardware
• Let’s first assume no paging in the system
• User generates logical addresses
• These addresses consist of a segment number and an
offset into the segment
• Use segment number to index into a table
• Table contains the physical address of the start of the
segment
– often called the base address
• Add the offset to the base and generate the physical
address
– before doing this, check the offset against a limit
– the limit is the size of the segment
10. Segmentation with Paging
• Most architectures support segmentation and paging
• Basic idea,
– segments exist in virtual address space
– base address in segment descriptor table is a
virtual address
– use paging mechanism to translate this virtual
address into a physical address
• Now an entire segment does not have to be in
memory at one time
– only the part of the segment that we need will be
in memory
13. Segment Protection
Protection: How does one process ensure that no
other process can access its memory? OS make sure
that it never creates a segment table entry that
points to same physical memory
15. Segmentation issue
• Entire segment is either in memory or on disk
• Variable sized segments leads to external
fragmentation in memory
• Must find a space big enough to place
segment into
• May need to swap out some segments to
bring a new segment in
17. Segmentation Over Paging
• Paging:
Fixed Size
Transparent to programmer (system allocates memory)
No separate protection
No separate compiling
No shared code
Internal Fragmentation take paces
• Segmentation:
Involves programmer (allocates memory to specific function inside code)
Separate compiling
Separate protection
Share code
Variable Size
Internal l Fragmentation does not take place