From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Haertel <mike@ducky.net>
Message-Id: <200301262125.h0QLPtmM097255@ducky.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] seek() in fossil?
In-Reply-To: <56bdfd682af03e2cf62bd4473efc7599@mightycheese.com>
Date: Sun, 26 Jan 2003 13:25:55 -0800
Topicbox-Message-UUID: 47dc6674-eacb-11e9-9e20-41e7f4b1d025

>This reminds me of the IPv6 fools, who seemed to think that
>if 2^48 wasn't quite enough, they should go for 2^64 but just
>to be sure, double it to 2^128.

You might argue that 2^128 is insanely wasteful, but it's also
awfully convenient.  It allows all sorts of sparse allocation schemes
for large blocks of addresses, without fear that you're using up
too much of the address space.  At 2^64, some Actual Thought might
be required in doling out large chunks of the address space.  At
2^128 there is definitely no Actual Thought required: you just waste
address space however happens to be most convenient.

Consider this: at 2^64, we couldn't even afford to give each person
their own 2^32 block, since there are already more than 2^32 humans.
While a 2^32 block per person might seem incredibly wasteful, it's
not a huge stretch to imagine technologies that might want such a
thing happening within say the next 30 years (device density is
still increasing exponentially).  I can't imagine what such
technologies might be, but I am sure not going to go on the record
as saying "nope, that's ridiculous, will never happen."

As a programmer, you must have experienced the analagous situation:
often you can make a tradeoff between simple code and larger data
size, or more complex code and smaller data size.  Now that memory
is cheap, the former choice is almost always preferable.  You end
up "wasting" memory, but you save a lot in terms of coding and
debugging effort.  Saving actual thought in global network address
allocation is a similarly worthy tradeoff.