The Implementation Of Shared Memory Can Be Done By Th 511019

The Implementation Of A Shared Memory Can Be Done By Three Main Me

The implementation of a shared memory can be done by three main methods: I. A multiplexed uniprocessor in which the runtime system and/or OS occasionally preempt and swap threads and there are interleaved with no parallelism mechanism II. Hardware multithreading where tolerate pipeline latencies and higher efficiency can happen. III. Multiprocessing where multiply execution resources and higher peak performance happen. Discuss two possible problems that may occur when using multiprocessors with a shared memory. Propose two different solutions to these problems. Consider the hardware and the software needed in your proposed solutions. Don’t try to find an existing solution in the market. The goal here is to think and propose your own solution.

Think of a topology as a network's virtual shape or structure. This shape does not necessarily correspond to the actual physical layout of the devices on the network. For example, the computers on a home LAN may be arranged in a circle in a family room, but it would be highly unlikely to find a ring topology there. What are the advantages and disadvantages of the processor network topologies? Identify the different applications and environments that are suitable for each physical topology. Is there a relationship between the computer network topologies and processor network topologies? Explain.

Questions for Analyzing a Genre:

• Who is the intended audience?
• What discourse community or (communities) is this audience in?
• What are these readers likely to know? want to know? why?
• How much time will this audience want to spend reading this document?
• What is the writer’s purpose?
• What does the writer want the reader(s) to do after reading?

Content:

• How does the writer select content material to achieve his/her purpose with this particular audience?
• What types of information are considered appropriate in this genre?
• What types of information would be considered inappropriate in this genre?
• What types of evidence are acceptable to support claims?

Structure:

• How much information is considered appropriate?
• What is a typical sequence for information in this genre?
• How is the structure serving the audience’s needs and the writer’s purpose?

Style/language (Linguistic):

• How formal or informal is the language?
• What specialized vocabulary is used?
• How long/short are sentences and paragraphs?
• What other language features do you notice?

Lab 5 –MIPS Assembly language Programming with MARS IDE Console Commands The purpose of this lab is to introduce you to the layout and structure of the Mars IDE development tool in addition to Array programming and console commands. In this lab, Fibonacci numbers are generated and printed in the console of the MIPS environment. Introduction: By definition, the first two numbers in the Fibonacci sequence are 0 and 1, and each subsequent number is the sum of the previous two. The Fibonacci numbers are: Procedure: I. Follow the same procedure in Lab1. II. From the main menu, choose “File†“Newâ€. III. Write the code provided in the screen shot below. The code: # ----------------------------Lab 5------------------------------------- #-----------------------Generate Fibonacci numbers---------------- #-----------------------Print on the MIPS console------------------- #-------------------------By: Dr. Abdallah--------------------------- # Compute several Fibonacci numbers and put in array, then print .data fibs:.word 0 : 19 # "array" of words to contain fib values size: .word 19 # size of "array" (agrees with array declaration) .text la $s0, fibs # load address of array la $s5, size # load address of size variable lw $s5, 0($s5) # load array size li $s2, 1 # 1 is the known value of first and second Fib. number sw $s2, 0($s0) # F[0] = 1 sw $s2, 4($s0) # F[1] = F[0] = 1 addi $s1, $s5, -2 # Counter for loop, will execute (size-2) times # Loop to compute each Fibonacci number using the previous two Fib. numbers. loop: lw $s3, 0($s0) # Get value from array F[n-2] lw $s4, 4($s0) # Get value from array F[n-1] add $s2, $s3, $s4 # F[n] = F[n-1] + F[n-2] sw $s2, 8($s0) # Store newly computed F[n] in array addi $s0, $s0, 4 # increment address to now-known Fib. number storage addi $s1, $s1, -1 # decrement loop counter bgtz $s1, loop # repeat while not finished # Fibonacci numbers are computed and stored in array. Print them. la $a0, fibs # first argument for print (array) add $a1, $zero, $s5 # second argument for print (size) jal print # call print routine. # The program is finished. Exit. li $v0, 10 # system call for exit syscall # Exit! ############################################################### # Subroutine to print the numbers on one line. .data space:.asciiz " " # space to insert between numbers head: .asciiz "The Fibonacci numbers are:\n" .text print:add $t0, $zero, $a0 # starting address of array of data to be printed add $t1, $zero, $a1 # initialize loop counter to array size la $a0, head # load address of the print heading string li $v0, 4 # specify Print String service syscall # print the heading string out: lw $a0, 0($t0) # load the integer to be printed (the current Fib. number) li $v0, 1 # specify Print Integer service syscall # print fibonacci number la $a0, space # load address of spacer for syscall li $v0, 4 # specify Print String service syscall # print the spacer string addi $t0, $t0, 4 # increment address of data to be printed addi $t1, $t1, -1 # decrement loop counter bgtz $t1, out # repeat while not finished jr $ra # return from subroutine # End of subroutine to print the numbers on one line ############################################################### · Observe the registers/Memory locations values after each Step Run. Questions: 1- What does the final value of $s2 represent? 2- What does the final value of $s3 represent? 3- What does the final value of $s4 represent? 4- What does the final value of $s5 represent? 5- Modify the code to generate 21 Fibonacci numbers Things to turn in as your Lab 5 Report, attached in this order: 1- Your name, Course Number, Lab Number and Date 2- Screen shot of the Program 3- Results/Observations such as the final screen shot of the registers and memory locations 4- Questions with answers

Paper For Above instruction

The provided instructions encompass two main topics: the implementation of shared memory in multiprocessor systems and the analysis of processor network topologies, along with a comprehensive overview of MIPS assembly programming for Fibonacci number generation using MARS IDE. This paper systematically explores these areas, offering in-depth explanations, problem-solving strategies, and practical programming insights.

Shared Memory in Multiprocessor Systems

Shared memory architecture is fundamental in multiprocessor systems, facilitating efficient communication and data sharing among processors. Its implementation can be approached through three primary methods: multiplexed uniprocessors, hardware multithreading, and multiprocessing. Each method has distinct characteristics influencing system performance and complexity.

Firstly, multiplexed uniprocessors alternate thread execution by preempting and swapping threads, interleaving tasks without automatic parallelism. While this approach simplifies hardware design, it can lead to problems such as thread starvation, where certain threads are perpetually preempted, causing delays or deadlocks in data access. A solution involves implementing a priority-based scheduling algorithm with fairness policies, where hardware and software collaborate to ensure that no thread is indefinitely postponed, perhaps through priority aging mechanisms that dynamically adjust thread priorities, promoting equitable access to shared memory.

Secondly, hardware multithreading involves multiple threads executing in a pipelined processor, tolerating pipeline latencies and increasing throughput. However, this approach introduces issues like cache contention and synchronization delays. To address cache contention, one possible solution is to design a hardware-assisted cache partitioning mechanism that isolates cache lines among threads, reducing conflicts. For synchronization delays, software-level barriers or lock-free algorithms can be implemented to minimize waiting times, requiring additional hardware support for atomic operations to ensure consistency.

Thirdly, multiprocessing systems incorporate multiple processing units with independent hardware resources, which maximize peak performance but pose significant challenges due to data consistency and coherence. One problem is cache coherence violations, where multiple caches hold inconsistent data. A solution is to develop a software-based directory protocol that tracks cache states and enforces coherence through explicit cache management routines. Another issue is contention for shared memory access, which can be mitigated by designing a hardware-supported memory arbitration mechanism coupled with software lock management routines that ensure orderly access, reducing race conditions and deadlocks.

Processor Network Topologies and Their Applications

Network topology defines the virtual arrangement of processors, impacting communication efficiency, scalability, and fault tolerance. Common topologies include ring, star, mesh, bus, and tree structures, each with unique advantages and disadvantages.

The ring topology facilitates simple, predictable communication with high fault tolerance, suitable for small clusters needing symmetrical data flow. Its disadvantages include potential for bottlenecks and latency issues as networks scale. Mesh topology offers high redundancy and parallel communication pathways, ideal for supercomputers requiring high throughput, but at increased hardware costs.

The star topology centralizes communication through a hub or switch, simplifying management and fault isolation, making it apt for data centers and enterprise networks. However, the hub becomes a critical point of failure. Bus topology, though inexpensive and easy to implement, suffers from limited scalability and data collisions, suitable for small, low-traffic systems.

The physical topology often influences the virtual topology of processor networks. For example, a mesh physical layout can support logical ring or grid structures to optimize communication pathways. Conversely, virtual topologies may differ from physical layouts to achieve better performance or fault tolerance, highlighting the intertwined relationship between the physical architecture and the logical structure of processor networks.

Analysis of Genre: Technical Documentation and Programming Reports

Technical documents serve specific audiences comprising engineers, programmers, and system architects. These readers typically possess a background knowledge of the domain, seeking detailed, precise information to guide implementation or problem-solving. The purpose is to inform, instruct, or propose solutions, prompting readers to apply knowledge or develop systems based on the provided data.

The selection of content is driven by relevance, clarity, and technical accuracy, emphasizing empirical evidence, specifications, algorithms, and practical examples. Inappropriate content includes vague descriptions, non-technical elaborations, or unsupported claims. Supporting evidence is primarily empirical data, hardware specifications, or algorithm analysis.

The structure follows logical sequencing—introduction, detailed explanation, problem identification, proposed solutions, illustrative examples, and conclusions—structured to serve clarity and usability. The language style tends to be formal, concise, and technical, incorporating domain-specific vocabulary, short and precise sentences, and clear paragraph delineation to optimize comprehension and engagement.

Programming and Assembly Language: Fibonacci Sequence with MARS IDE

The Lab 5 exercise demonstrates programming in MIPS assembly language within the MARS IDE, focusing on generating and printing Fibonacci numbers. The assembly code initializes an array to store Fibonacci numbers, computes subsequent values iteratively, and employs subroutines to print the results. The process emphasizes understanding register operations, memory addressing, and control flow in assembly language.

The code begins with data declaration, defining an array for Fibonacci numbers and its size. The main program loads the array’s address, initializes known Fibonacci values (0 and 1), and iterates to compute further numbers, storing them sequentially. The print subroutine outputs a heading, each Fibonacci number, and spacing, utilizing system calls for string and integer output. Observing register values after execution reveals insights into how data propagates through registers and memory during computation.

The final value of specific registers like $s2, $s3, $s4, and $s5 reflect the latest Fibonacci number computed, the second last, the third last, and the size of the array, respectively. Modifying the code to generate 21 Fibonacci numbers involves adjusting the array size and loop counter, which enhances understanding of assembly control structures and data management for scalable numeric computations.

Conclusion

This comprehensive review underscores the significance of shared memory architectures, network topologies, and low-level programming in computing systems. By analyzing problems and proposing innovative solutions, alongside understanding assembly language intricacies, practitioners and researchers can optimize system performance, reliability, and scalability. Embracing such technical insights fosters advancements across multiprocessor designs, network configurations, and embedded programming domains, driving technological progress.

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