Back-of-the-envelope cost of extra data :-)

Olson, Arthur David (NIH/NCI) olsona at dc37a.nci.nih.gov
Wed May 4 16:09:51 UTC 2005


This output...
	Script started on Wed 04 May 2005 10:15:00 AM EDT
	lecserver$ du -s tz*/tmp/*/zoneinfo
	489	tz/tmp/etc/zoneinfo
	1709	tzexp/tmp/etc/zoneinfo
	lecserver$ exit

	script done on Wed 04 May 2005 10:15:08 AM EDT
...indicates that "old-format" data eats up about half a megabyte of disk
space total while "new-format" data eats up about 2 megabytes.
(Some individual files grow by a factor of 9; others don't grow at all; the
final result lies between these extremes.)
At a dollar per gigabyte of disk space, the old stuff costs one twentieth of
a cent per computer while the new stuff costs four twentieths of a cent per
computer, for a difference of three twentieths of a cent.

Making a wild estimate of one computer per person, there are about 6.5
billion computers in the world.
In this case I'm happy if 90% are running Windows, since Microsoft doesn't
ship time zone files.
That leaves at most 650 million computers where the time zone files might
show up.
Maximum total cost: 650 million computers * three twentieths of a cent:
$975,000 (ulp!)

Frightening corollary: 1024 bytes of Microsoft code bloat costs the world
economy $5850.

				--ado






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