Performance
Page faults, by their very nature, degrade the performance of a program or operating system and in the degenerate case can cause thrashing. Optimizations to programs and the operating system that reduce the number of page faults improve the performance of the program or even the entire system. The two primary focuses of the optimization effort are reducing overall memory usage and improving memory locality. Generally, making more physical memory available also reduces page faults. Many page replacement algorithms have been proposed, such as implementing heuristic-based algorithms to reduce the incidence of page faults.
An average hard disk has an average rotational latency of 3ms, a seek-time of 5ms, and a transfer-time of 0.05ms/page. So the total time for paging comes in near 8ms (8 000 000 ns). If the memory access time is 200ns, then the page fault would make the operation about 40,000 times slower. To reduce the page faults in the system, programmers must make use of an appropriate page replacement algorithm that suits the current requirements and maximizes the page hits.
Read more about this topic: Page Fault
Famous quotes containing the word performance:
“The honor my country shall never be stained by an apology from me for the statement of truth and the performance of duty; nor can I give any explanation of my official acts except such as is due to integrity and justice and consistent with the principles on which our institutions have been framed.”
—Andrew Jackson (1767–1845)
“The child to be concerned about is the one who is actively unhappy, [in school].... In the long run, a child’s emotional development has a far greater impact on his life than his school performance or the curriculum’s richness, so it is wise to do everything possible to change a situation in which a child is suffering excessively.”
—Dorothy H. Cohen (20th century)
“Nobody can misunderstand a boy like his own mother.... Mothers at present can bring children into the world, but this performance is apt to mark the end of their capacities. They can’t even attend to the elementary animal requirements of their offspring. It is quite surprising how many children survive in spite of their mothers.”
—Norman Douglas (1868–1952)