:> :can you detail in more clarity the flip-flopping you were seeing?
:>     Basically what is happening is that switch/wakeup overhead is being
:>     imposed unnecessarily.  There is no need to switch if there is nothing
:>     to switch to, and this also causes the other process to not have to
:>     wakeup anyone when it releases Giant because process #1 is spinning
:>     on it instead of sleeping on it.  So you immediate remove four context
:>     switches from the critical path.
:true, though the original code would halt the processor to reduce power
:consumption on laptops etc. procrunnable doesn't include the idle
:process. (a side-effect).

    That would still work, the spin only occurs when multiple cpus are vying
    for a sleep lock.  But it's moot now, something isn't working as expected.
    It's as though procrunnable() is broken.

                                        Matthew Dillon 
                                        <[EMAIL PROTECTED]>

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