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Unformatted text preview: string ”hello,world\n”, originally on disk, is copied to main memory, and then copied from main memory to the display device. From a programmer’s perspective, much of this copying is overhead that slows down the “real work” of the program. Thus, a major goal for system designers is make these copy operations run as fast as possible. Because of physical laws, larger storage devices are slower than smaller storage devices. And faster devices are more expensive to build than their slower counterparts. For example, the disk drive on a typical system might be 100 times larger than the main memory, but it might take the processor 10,000,000 times longer to read a word from disk than from memory. Similarly, a typical register ﬁle stores only a few hundred of bytes of information, as opposed to millions of bytes in the main memory. However, the processor can read data from the register ﬁle almost 100 times faster than from memory. Even more troublesome, as semiconductor technology progres...
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- Spring '10
- The American