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From: Julien Ridoux <jrid@cubinlab.ee.unimelb.edu.au>
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Date: Wed, 9 Nov 2011 23:12:35 +1100
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Subject: [RFC] Feed-Forward Clock support
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Hi all,

I have written a set of patches to support feed-forward clock =
synchronisation algorithms. To cut a long story short, this work =
provides support for alternatives to the NTP daemon. The RADclock daemon =
we developed is one of these alternatives.

This work is supported by the FreeBSD Foundation and a short project =
description can be found here:
http://www.freebsdfoundation.org/press/2011Aug-newsletter.shtml#Project4

The patches will be committed on the weekend of Nov 19th and suggestions =
and comments would be very appreciated.

The patches against r227382 can be found at this URL:
http://www.cubinlab.ee.unimelb.edu.au/~jrid/ffclock_fbsd_r227382.tar.gz

The patches introduce 3 new system calls and it is then necessary to run =
'make sysent' in sys/kern and sys/compat/freebsd32.
The feed-forward support can be compiled by adding the FFCLOCK option to =
the kernel configuration file.

For more information, a fairly high level description of the =
feed-forward approach for clock synchronisation is given in this ACM =
Queue article.
http://queue.acm.org/detail.cfm?id=3D1773943

All relevant technical papers, the latest stable RADclock version and =
more can be found here:
http://www.synclab.org/radclock/

Please let me know your thoughts,

Thanks,
Julien