Neil Conway <neilc(at)samurai(dot)com> writes:
> POSIX_FADV_RANDOM doesn't effect the page cache, it just determines how
> aggressive the kernel is when doing readahead (at least on Linux, but
> I'd expect to see other kernels implement similar behavior).
I would expect POSIX_FADV_SEQUENTIAL to reduce the chance that a page
will be kept in buffer cache after it's been used.
regards, tom lane