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    SubjectRe: [PATCH 00/19] Adaptive read-ahead V8
    On Fri, Nov 25, 2005 at 04:43:17PM +0100, Diego Calleja wrote:
    > Recently, a openoffice hacker wrote in his blog that the kernel was
    > culprit of applications not starting as fast as in other systems.
    > Most of the reasons he gave were wrong, but there was a interesting
    > one: When you start your system, you've lots of free memory. Since
    > you have lots of memory, he said it was reasonable to expect that
    > kernel would readahead *heavily* everything it can to fill that
    > memory as soon as possible (hoping that what you readahead'ed was
    > part of the kde/gnome/openoffice libraries etc) and go back to the
    > normal behaviour when your free memory is used by caches etc.
    > "Teorically" it looks like a nice heuristic for desktops. Does
    > adaptative readahead does something like this?

    It's interesting ;)
    In fact some distributions do have a read-ahead script to preload files on
    startup. The readahead system call should be enough for this purpose:

    NAME
    readahead - perform file readahead into page cache

    SYNOPSIS
    #include <fcntl.h>

    ssize_t readahead(int fd, off64_t *offset, size_t count);

    Thanks,
    Wu
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