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    User name R. Michaels

    Log entry time 09:51:48 on June 1,2000

    Entry number 42729

    This entry is a followup to: 42690

    keyword=mods to spot (re: deadtime)

    I modified spot so that it sleeps 5 msec every 100 events.
    Previous experience shows that if any code reads from the same
    disk that we are writing to, at high rates (>1.5 kHz), it causes
    deadtime. The disk head jumps around.

    The long-term solution is to use ET system everywhere.
    DHIST already uses ET, and I believe Mark Jones installed it
    in the counting room version of ESPACE (one must "turn it on").
    Also the copy algorithm (etcopy) to MSS spies on ET and should
    not cause deadtime. "hana" does not use ET.

    Spot does not have ET yet, so the above "sleep" trick is a quick
    and dirty fix. It does not sleep if you specify a file (spot -f filename)
    on the assumption that filename is not on the present disk.