Messages in this thread | | | Subject | Re: mmap() is slower than read() on SCSI/IDE on 2.0 and 2.1 | Date | Mon, 14 Dec 1998 20:54:23 -0800 | From | "Jay Nordwick" <> |
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>I'd say that most apps use a fixed "buffer size". "cat" or "dd" use >0.5 to 8k buffers. That's constant buffer. >
With read() you can know that requests are coming in PAGE_SIZE*n, n>1, so you can prefetch more than a singe page. With mmap() that information is lost, you only see read os PAGE_SIZE.
> Roger. >
-jay
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