Software is more like a living being than an inanimate object. Just like living beings in the physical works, it must bend and adapt with time. This is becoming increasingly true with commodity hardware and the Internet of Things. IoT or not, what we’re really building are stateful and distributed systems that have a life of their own.

1. Mike Pack
@mikepack_
@mikepack
Time is the Only Hard Thing
in Computer Science

2. https://softsolder.com/2017/03/24/quartz-tuning-fork-resonator-teardown/

3. https://iamchaitanya.wordpress.com/2015/07/17/atomic-clocks/

4. https://phys.org/news/2013-08-nist-ytterbium-atomic-clocks-stability.html

5. https://en.wikipedia.org/wiki/Paranal_Observatory

6. Time

7. Time
Physical

8. Time
Physical
Distributed

9. Title TextPhysical Time

10. “There are only two hard things in Computer
Science: cache invalidation and naming
things.”
Phil Karlton

11. https://en.wikipedia.org/wiki/Cache_coherence#/media/File:Cache_Coherency_Generic.png

12. “My first remark is that, although the
programmer’s activity ends when he has
constructed a correct program, the process
taking place under control of his program is
the true subject matter of his activity”
Edsger W. Dijkstra
A Case against the GO TO Statement - 1968
http://www.cs.utexas.edu/users/EWD/ewd02xx/EWD215.PDF

13. “Our intellectual powers are rather geared to master
static relations and that our powers to visualize
processes evolving in time are relatively poorly
developed. For that reason we should do our utmost
to shorten the conceptual gap between the static
program and the dynamic process, to make the
correspondence between the program (spread out in
text space) and the process (spread out in time) as
trivial as possible.”
http://www.cs.utexas.edu/users/EWD/ewd02xx/EWD215.PDF

14. A = 0
LABEL: FOO
A += 1
PRINT A
GOTO FOO
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A = 0
INC(A)
DEF INC(A)
A += 1
PRINT A
INC(A)
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16. Title TextDistributed Time

17. Computer A
Computer B
Time →
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7

18. Demo

19. Title TextConclusion

20. The Internet of Things will multiply possibilities
as part of the Fourth Industrial Revolution.
World Economic Forum
https://www.weforum.org/agenda/2016/01/the-fourth-industrial-revolution-what-it-means-and-how-to-respond/

21. Title Text
https://www.pinterest.com/pin/550213279448097250

22. Mike Pack
@mikepack_
@mikepack
Thanks!