Re: [dhcwg] DHCP Process Time

Karl Auer <kauer@biplane.com.au> Wed, 28 September 2016 11:35 UTC

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From: Karl Auer <kauer@biplane.com.au>
To: dhcwg@ietf.org
Date: Wed, 28 Sep 2016 21:35:13 +1000
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Subject: Re: [dhcwg] DHCP Process Time
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On Wed, 2016-09-28 at 12:21 +0100, Simon Hobson wrote:
> Karl Auer <kauer@biplane.com.au> wrote:
> > Not quite sure what you mean, but there would seem to be four
> > obvious methods to look at the protocol and compare before and
> > after:
> 
> I can't help thinking that the overhead of handling just one extra
> option would be completely lost in the natural variation in timing. 

Yes - but I just didn't really know the OP meant. I think your
interpretation - that the OP wanted to compare the processing time with
and without a particular option - is probably correct.

As is your thought that the processing cost for one option is probably
negligible compared to other overheads. On the other hand, we don't
know what server is being used or what the special option is. Maybe it
makes more sense than we think. Maybe the OP is just being diligent and
making no assumptions about the effects of adding this option.

We run the Nominum DCS server, which has hooks for user-supplied code,
and it's certainly possible for that to chew a lot of CPU if we get it
wrong.

Regards, K.

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Karl Auer (kauer@biplane.com.au)
http://www.biplane.com.au/kauer
http://twitter.com/kauer389

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