**8.9. IBM System/370 Architecture Overview**The IBM System/370 architecture utilizes a two-level memory structure, often described as segments and pages. Although this segmentation approach lacks several features mentioned earlier in this chapter, it serves a purpose in memory management. For the basic 370 architecture:- The page size can be either 2 KB or 4 KB.- The segment size is fixed at either 64 KB or 1 MB.For the 370/XA and 370/ESA architectures:- The page size is standardized at 4 KB.- The segment size is fixed at 1 MB.**Discussion Points:**- What are the potential disadvantages of this segmentation scheme?- What benefits does segmentation offer to the 370 architecture? **8.7.** In the VAX, user page tables are located at virtual addresses in the system space. What is the advantage of having user page tables in virtual rather than main memory? What is the disadvantage?*Explanation:*In the VAX computer architecture, user page tables can be stored at virtual addresses within the system space rather than directly in main memory. This setup has certain advantages and disadvantages:**Advantages:**1. **Increased Flexibility:** By using virtual addresses, the system can more flexibly manage memory, allowing for more efficient use of available memory resources.2. **Protection:** Storing page tables at virtual addresses can improve protection against unauthorized access, as it enables the system to apply access controls and permissions more effectively.**Disadvantages:**1. **Additional Overhead:** Managing page tables at virtual addresses can introduce additional computational overhead, as it requires translating virtual addresses to physical addresses.2. **Potential For Increased Latency:** Accessing page tables in virtual memory might increase latency compared to direct access in physical memory, potentially affecting system performance.

Answered: 8.7. In the VAX, user page tables are…

8.7. In the VAX, user page tables are located at virtual addresses in the system space. What is the advantage of having user page tables in virtual rather than main memory? What is the disadvantage?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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HELP! You have a virtual memory system with a two-entry TLB, a 2-way set associative cache and a page table for a process P. Assume cache blocks of 8 bytes and page size of 16 bytes. In the system below, main memory is divided up into blocks, where each block is represented by a letter. Two blocks equals one frame. a)Virtual address page 3, offset 7 results in a TLB hit or miss? If TLB hit, what’s the main memory frame? If TLB miss, would it result in a page fault? If not a page fault, what’s the main memory frame and what the physical address in binary? Explain your answers. b)Virtual address page 0, offset 1310 results in a TLB hit or miss? If TLB hit, what’s the main memory frame? If TLB miss, would it result in a page fault? If not a page fault, what’s the main memory frame? Explain your answers. c)Virtual address page 2, offset 3 results in a TLB hit or miss? If TLB hit, what’s the main memory frame? If TLB miss, would it result in a page fault? If not a page fault, what’s the…
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