Lecture 17: Virtual Machines Virtual Machine Monitors What is a
... VMM can control the rate of timer interrupts to OS Can change how OS interprets passage of time If VMM slows timer by 10x, then other hardware (CPU, disk, network) appears 10x faster to OS and applications Can experiment with apps, protocols, and systems on future hardware ...
... VMM can control the rate of timer interrupts to OS Can change how OS interprets passage of time If VMM slows timer by 10x, then other hardware (CPU, disk, network) appears 10x faster to OS and applications Can experiment with apps, protocols, and systems on future hardware ...
lec17-memoryhier2
... • If plan for VM during design of ISA, easy to reduce instructions executed by VMM, speed to emulate – ISA is virtualizable if can execute VM directly on real machine while letting VMM retain ultimate control of CPU: “direct execution” – Since VMs have been considered for desktop/PC server apps only ...
... • If plan for VM during design of ISA, easy to reduce instructions executed by VMM, speed to emulate – ISA is virtualizable if can execute VM directly on real machine while letting VMM retain ultimate control of CPU: “direct execution” – Since VMs have been considered for desktop/PC server apps only ...
Chapter 3 Memory Management: Virtual Memory
... • Memory Map tables can be extremely large • Consider 32 bit machines which can address 4GB of memory – 232 = 4GB address space – with 4-KB page size => 1 million pages – That means a table with 1-million entries – Note: On the new 64 bit machines the (e.g. Linux) kernel supports a larger 2 million ...
... • Memory Map tables can be extremely large • Consider 32 bit machines which can address 4GB of memory – 232 = 4GB address space – with 4-KB page size => 1 million pages – That means a table with 1-million entries – Note: On the new 64 bit machines the (e.g. Linux) kernel supports a larger 2 million ...
Virtual machine - Duke Computer Science
... Transfer control to something that can do it Rewrite code Evaluate whether thing is allowed If so, do it and return control. Else, kill process or throw exception. ...
... Transfer control to something that can do it Rewrite code Evaluate whether thing is allowed If so, do it and return control. Else, kill process or throw exception. ...
1. What is the voltage across the 20Ω resistor? a. 0 V b. 2 V c. 3 V d
... photodiode operates in which quadrant of the IV characteristic curve (shown at the bottom of the page)? Assume that the reverse bias current is less than 100 O and the turn on voltage is less than 1 V. a. Quadrant A delivering (sourcing) power. b. Quadrant B delivering (sourcing) power. c. Quadrant ...
... photodiode operates in which quadrant of the IV characteristic curve (shown at the bottom of the page)? Assume that the reverse bias current is less than 100 O and the turn on voltage is less than 1 V. a. Quadrant A delivering (sourcing) power. b. Quadrant B delivering (sourcing) power. c. Quadrant ...
Single Address Space Operating Systems
... – communications support for numerous large program modules – sharing and protection support for a huge distributed database ...
... – communications support for numerous large program modules – sharing and protection support for a huge distributed database ...
Chapter 10 Exercises and Answers
... What is virtual memory and how does it apply to demand paging? Virtual memory is the illusion that memory is limitless and thus there is no limit on the size of a program. Demand paging is the technique where pages are brought into memory only when they are referenced (needed). Demand paging allows ...
... What is virtual memory and how does it apply to demand paging? Virtual memory is the illusion that memory is limitless and thus there is no limit on the size of a program. Demand paging is the technique where pages are brought into memory only when they are referenced (needed). Demand paging allows ...
Virtual machine - Duke Computer Science
... Support for legacy applications Do not force users to use a particular language Do not force users to use a particular OS ...
... Support for legacy applications Do not force users to use a particular language Do not force users to use a particular OS ...
Inside and Outside the OS
... Page table Keeps track of what is in memory and what is still out on hard disk Chapter 15 The Internal Operating System – Part 1 ...
... Page table Keeps track of what is in memory and what is still out on hard disk Chapter 15 The Internal Operating System – Part 1 ...
operating systems memory management
... allocated physical memory whenever that memory is available and the program needs it. Divide physical memory into fixed-sized blocks called frames (size is power of 2, between 512 bytes and 8192 bytes). Divide logical memory into blocks of same size called pages. Keep track of all free frames. To ru ...
... allocated physical memory whenever that memory is available and the program needs it. Divide physical memory into fixed-sized blocks called frames (size is power of 2, between 512 bytes and 8192 bytes). Divide logical memory into blocks of same size called pages. Keep track of all free frames. To ru ...
Mem_Mgmt
... allocated physical memory whenever that memory is available and the program needs it. • Divide physical memory into fixed-sized blocks called frames (size is power of 2, between 512 bytes and 8192 bytes). • Divide logical memory into blocks of same size called pages. • Keep track of all free frames. ...
... allocated physical memory whenever that memory is available and the program needs it. • Divide physical memory into fixed-sized blocks called frames (size is power of 2, between 512 bytes and 8192 bytes). • Divide logical memory into blocks of same size called pages. • Keep track of all free frames. ...
Linux-Spr-2001-sect-1-group
... Page Replacement – Modified version of Simple Clock Algorithm • Use bit replaced with an 8 bit age variable. • Age variable incremented every time page is accessed. • Age variable decremented periodicall by Linux • Larger the page variable, less likely it will be replaced Kernel memory allocation – ...
... Page Replacement – Modified version of Simple Clock Algorithm • Use bit replaced with an 8 bit age variable. • Age variable incremented every time page is accessed. • Age variable decremented periodicall by Linux • Larger the page variable, less likely it will be replaced Kernel memory allocation – ...
15.a The Internal Operating System
... Page table Keeps track of what is in memory and what is still out on hard disk Chapter 15 The Internal Operating System – Part 1 ...
... Page table Keeps track of what is in memory and what is still out on hard disk Chapter 15 The Internal Operating System – Part 1 ...
ppt
... Types of VMs – Emulation • Another (older) way for running one OS on a different OS • Virtualization requires underlying CPU to be same as guest was compiled for while Emulation allows guest to run on different CPU ...
... Types of VMs – Emulation • Another (older) way for running one OS on a different OS • Virtualization requires underlying CPU to be same as guest was compiled for while Emulation allows guest to run on different CPU ...
OperatingSystems_FA15_8_Memory
... Permits the Physical Address Space of Process to be Noncontiguous. Avoids Memory External Fragmentation and Compaction. Avoids Backing Store Fragmentation. Frames: Physical Memory partitioned into fixed-size blocks ...
... Permits the Physical Address Space of Process to be Noncontiguous. Avoids Memory External Fragmentation and Compaction. Avoids Backing Store Fragmentation. Frames: Physical Memory partitioned into fixed-size blocks ...
ch9
... Hole – variable size block of available memory new process is allocated memory from a hole Operating system maintains information about: a) allocated partitions b) free partitions (holes) ...
... Hole – variable size block of available memory new process is allocated memory from a hole Operating system maintains information about: a) allocated partitions b) free partitions (holes) ...
True
... 7. T / F – In the Dynamic Partitioning technique of memory management, the bestfit placement algorithm is usually the best performer of the available algorithms. 8. T / F – In the Dynamic Partitioning technique of memory management, compaction refers to shifting the processes into a contiguous block ...
... 7. T / F – In the Dynamic Partitioning technique of memory management, the bestfit placement algorithm is usually the best performer of the available algorithms. 8. T / F – In the Dynamic Partitioning technique of memory management, compaction refers to shifting the processes into a contiguous block ...
μ-kernels Advantages Disadvantages Primitives in a μ
... reduced memory protection. If a user extension exceeds its memory allocations, the extension may damage the kernel memory. – Extensions has to be written in a special language (Modula-3) in order to check memory exceeding, but • The checking is time consuming. (The CPU checks memory exceeding, inste ...
... reduced memory protection. If a user extension exceeds its memory allocations, the extension may damage the kernel memory. – Extensions has to be written in a special language (Modula-3) in order to check memory exceeding, but • The checking is time consuming. (The CPU checks memory exceeding, inste ...
COS 318: Operating Systems Virtual Machine Monitors Jaswinder Pal Singh
... l Perform Binary Translation (Full Virtualization) l Note: both basically remove problematic (nonvirtualizable) instructions from the guest OS l ...
... l Perform Binary Translation (Full Virtualization) l Note: both basically remove problematic (nonvirtualizable) instructions from the guest OS l ...
Spotlight on Terminology and Language – ESL Pointers
... Page 396 “If personality consisted only of primitive, instinctual cravings and longings, it would have just one component: the id. The id is the raw, unorganized, inborn part of personality.” ...
... Page 396 “If personality consisted only of primitive, instinctual cravings and longings, it would have just one component: the id. The id is the raw, unorganized, inborn part of personality.” ...
Design Tradeoffs For Software
... The virtual to physical address translation operation sits on the critical path between the CPU and the cache. If every request for a memory location out from the processor required one or more accesses to main memory (to read page table entries), then the processor would be very slow. ...
... The virtual to physical address translation operation sits on the critical path between the CPU and the cache. If every request for a memory location out from the processor required one or more accesses to main memory (to read page table entries), then the processor would be very slow. ...
Copyright © 1997 IEEE. Reprinted from Proceedings of the Third
... for dynamic growth. In contrast, the 4.3BSD UNIX [34] address space was composed of two continuous regions, depicted in Fig 1. This arrangement allowed the user page tables to occupy minimal space, which was important because the original virtual memory design did not allow the page tables to be pag ...
... for dynamic growth. In contrast, the 4.3BSD UNIX [34] address space was composed of two continuous regions, depicted in Fig 1. This arrangement allowed the user page tables to occupy minimal space, which was important because the original virtual memory design did not allow the page tables to be pag ...
Section 29: Electric Circuits
... CiE iGCSE Physics 0625 Learning Plan Section 29: Electric Circuits Specification Resources Core Draw and interpret circuit diagrams containing sources, switches, resistors (fixed and variable), heaters, thermistors, lightdependent resistors, lamps, ammeters, voltmeters, galvanometers, magnetising ...
... CiE iGCSE Physics 0625 Learning Plan Section 29: Electric Circuits Specification Resources Core Draw and interpret circuit diagrams containing sources, switches, resistors (fixed and variable), heaters, thermistors, lightdependent resistors, lamps, ammeters, voltmeters, galvanometers, magnetising ...
Memory management unit
A memory management unit (MMU), sometimes called paged memory management unit (PMMU), is a computer hardware unit having all memory references passed through itself, primarily performing the translation of virtual memory addresses to physical addresses. It is usually implemented as part of the central processing unit (CPU), but it also can be in the form of a separate integrated circuit.An MMU effectively performs virtual memory management, handling at the same time memory protection, cache control, bus arbitration and, in simpler computer architectures (especially 8-bit systems), bank switching.