64bit ticks, was Re: Changing p_swtime and td_slptime to ticks

[Garrett Wollman]

Jeff Roberson writes:

>Is there a good reason for not making ticks 64bit?  math involving this 
>value is relatively infrequent.  Bruce?  Any comments?  It'd sure let us 
>forget all of these counter wrapping problems.

Making ticks 64 bits on 32-bit architectures means that updates to it
will not be atomic.

-GAWollman

-- 
Garrett A. Wollman   | The real tragedy of human existence is not that we are
wollman at csail.mit.edu| nasty by nature, but that a cruel structural asymmetry
Opinions not those   | grants to rare events of meanness such power to shape
of MIT or CSAIL.     | our history. - S.J. Gould, Ten Thousand Acts of Kindness