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    Subjectgettimeofday order of magnitude slower with pmtimer, which is default
    Hi everybody,

    For my open source nameserver ( I need to do quite a
    number of gettimeofday calls. I've pared it down to almost the bare minimum
    of 1 gettimeofday per packet sent and received. With these calls, I can make
    stats like which my users need so they can verify
    the proper performance of the nameserver.

    Yesterday, together with Zwane, I discovered each gettimeofday call costs me
    4 usec on some boxes and almost nothing on others. We did a fruitless chase
    for vsyscall/sysenter happening but the problem turned out to be

    This problem has been discussed before

    Not only is the pm timer slow by design, it also needs to be read multiple
    times to work around a bug in certain hardware.

    What is new is that this option is now dependent on CONFIG_EMBEDDED. Unless
    you select this option, the PM Timer will always be used.

    Would a patch removing the link to EMBEDDED and adding a warning that while
    this timer is of high quality, it is slow, be welcome?


    -- Open source, database driven DNS Software Open and Closed source services
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      Last update: 2006-03-20 13:27    [W:0.042 / U:93.012 seconds]
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