Mel wrote:
> - mark -= mark / 2; [A]
> + mark /= 2; [B]
> if (alloc_flags & ALLOC_HARDER)
> - mark -= mark / 4; [C]
> + mark /= 4; [D]
Why these changes? For each of [A] - [D] above, if I start with a
value of mark == 33 and recycle that same mark through the above
transformation 16 times, I get the following sequence of values:
A: 33 17 9 5 3 2 1 1 1 1 1 1 1 1 1 1
B: 33 16 8 4 2 1 0 0 0 0 0 0 0 0 0 0
C: 33 25 19 15 12 9 7 6 5 4 3 3 3 3 3 3
D: 33 8 2 0 0 0 0 0 0 0 0 0 0 0 0 0
Comparing [A] to [B], observe that [A] converges to 1, but [B] to 0,
due to handling the underflow differently.
Comparing [C] to [D], observe that [D] converges to 0, due to the
different underflow, and converges much faster, since it is taking off
3/4's instead of 1/4 each iteration.
I doubt you want this change.
--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <[email protected]> 1.925.600.0401
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