Collecting entropy from device_attach() times.

[Dag-Erling Smørgrav]

Dag-Erling Smørgrav <des at des.no> writes:
> If you give me a couple of days, I'll try to come up with a patch that
> collects and stores attach times during boot so we can gather and
> analyse real data.

Here's the data:

  http://people.freebsd.org/~des/attachtimes-text.txz

The tarball contains one directory for each machine I collected data
from.  Inside each directory is a separate text file for each device in
the system.  Each text file contains the attachtime deltas for that
device, one sample per line.

I also included the kernel patch and the source code of the program used
to extract the data.

The total number of experiments is

    6250 elitebook
    7228 epia1
    6803 epia2
    4034 thinkpad
   13261 virtualbox
   37576 total

with a total of 2485193 samples.

Please ignore atkbd0 and atkbdc0, at least for epia1 and epia2, as they
only appear when a keyboard is connected.

I also uploaded a tarball with the raw data:

  http://people.freebsd.org/~des/attachtimes-bin.txz

DES
-- 
Dag-Erling Smørgrav - des at des.no