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[[!tag open_issue_gnumach open_issue_hurd]]

IRC, #hurd, freenode, 2011-02-13:

    <etenil> youpi: Would libdiskfs/diskfs.h be in the right place to make
      readahead functions?
    <youpi> etenil: no, it'd rather be at the memory management layer,
      i.e. mach, unfortunately
    <youpi> because that's where you see the page faults
    <etenil> youpi: Linux also provides a readahead() function for higher level
      applications. I'll probably have to add the same thing in a place that's
      higher level than mach
    <youpi> well, that should just be hooked to the same common implementation
    <etenil> the man page for readahead() also states that portable
      applications should avoid it, but it could be benefic to have it for
      portability
    <youpi> it's not in posix indeed

IRC, #hurd, freenode, 2011-02-14:

    <etenil> youpi: I've investigated prefetching (readahead) techniques. One
      called DiskSeen seems really efficient. I can't tell yet if it's patented
      etc. but I'll keep you informed
    <youpi> don't bother with complicated techniques, even the most simple ones
      will be plenty :)
    <etenil> it's not complicated really
    <youpi> the matter is more about how to plug it into mach
    <etenil> ok
    <youpi> then don't bother with potential pattents
    <antrik> etenil: please take a look at the work KAM did for last year's
      GSoC
    <youpi> just use a trivial technique :)
    <etenil> ok, i'll just go the easy way then

    <braunr> antrik: what was etenil referring to when talking about
      prefetching ?
    <braunr> oh, madvise() stuff
    <braunr> i could help him with that