Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
As mentioned above, page tables, are lookup tables mapping a process' virtual pages to physical pages in RAM. How would one implement these page tables?
The most straightforward approach would simply have a single linear array of page-table entries (PTEs). Each PTE contains information about the page, such as its physical page number ("frame" number) as well as status bits, such as whether or not the page is valid, and other bits to be discussed later.
If we have a 32-bit architecture with 4k pages, then we have 2 pages, as discussed in the last lecture. If each PTE is 4 bytes, then each page table requires 4 Mbytes of memory. And remember that each process needs its own page table, and theremay be on the order of 100 processes running on a typical personal computer. This would require on the order of 400 Mbytes of RAM just to hold the page tables on a typical desktop!
Furthermore, many programs have a very sparse virtual address space. The vast majority of their PTEs would simply be marked invalid.Clearly, we need a better solution than single-level page tables.
What is a Process Control Block? Every process in the operating system is represented by a process control block as well called a task control block. It contains several pieces
Q. What protection problems may occur if a shared stack is used for parameter passing? Answer: The contents of the stack could be conciliation by other process(es) sharing th
Q. Explain about Deadlocks? Deadlocks for (int i = 0; i // first find a thread that can finish for (int j = 0; j if (!finish[j]) { boolean temp = true; for
Q. How does DMA raise system concurrency? How does it make difficult hardware design? Answer: DMA increases system concurrency by allowing the CPU to perform tasks while the
Explain the ExitThread Function used in the Windows NT ExitThread(ExitCode) The ExitThread( ) call is made to end the currently running thread. If the current thread is th
What is a pure demand paging? When starting implementation of a process with no pages in memory, the operating system sets the instruction pointer to the first instruction of t
what do you mean by starvation?explain in detail
describe competing process
why we say " OS is a resource allocator" and “OS is a control program"?
Several schemes available are as follows: Pipes : One-way communication process through which different process can interact. The problem is that the two processes could have
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd