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Re: 9.1: boot-time delay?

Last week, I wrote, here, of a delay when booting 9.1

>>> [     3.288539] uhub2: 4 ports with 4 removable, self powered
>>> [     3.288539] uhub3: 6 ports with 6 removable, self powered
>>> [    25.272567] wd0 at atabus0 drive 0
>>> [    25.273568] wd0: <ST500DM002-1BD142>

and, in a later mail,

> [A]s soon as I sent my mail and started looking at subsetting diffs,
> I discovered the diffs between the installer kernel and the
> operational kernel were far smaller than I remembered (and mostly
> irrelevant):

It looks as though this, of all things, is the relevant line:

> +options 	HZ=8000

My first reaction is that something somewhere is delaying by a fixed
number of ticks rather than doing arithmetic with hz, but that would
make the difference go in the other direction.  I'm having trouble
coming up with a plausible scenario that would explain the delay
getting _longer_ with HZ=8000.  The most plausible thing I've thought
of is that some delay is being computed based on hz and then getting
treated as milliseconds instead of ticks or some such and getting
multiplied by hz again.

Anyone have any thoughts on possible ways to track this one down?  I'm
going to be doing what I can, but any thoughts anyone has would be
welcomed; I am only minimally familiar with 9.1's kernel internals.

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