Re: mmap vs fs cache

Phillip Susi
2013-03-09T01:22:23Z

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On 03/08/2013 10:00 AM, Howard Chu wrote:
> Yes, that's what I was thinking. I added a
> posix_madvise(..POSIX_MADV_RANDOM) but that had no effect on the
> test.

Yep, that's because it isn't implemented.

You might try MADV_WILLNEED to schedule it to be read in first. I
believe that will only read in the requested page, without additional
readahead, and then when you fault on the page, it already has IO
scheduled, so the extra readahead will also be skipped.

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