The document discusses the Milkyway@Home distributed computing project which uses volunteer computing to work on simulations of the structure of the Milky Way galaxy, including tidal streams and N-body simulations. It also discusses development of iOS and mobile apps for the project, optimizations made to the CAL++ code to speed up simulations, issues that arose from updating the project's Subversion server software, plans to implement simulations using the Lua programming language, and work done on GPU implementations of the N-body problem.

1. Milkyway@Home
Friday, April 8, 2011

2. Milkyway@Home
• Distributed computing project
• Work on structure of Milkyway
• Tidal streams
• N-body simulation
Friday, April 8, 2011

3. Friday, April 8, 2011

4. Friday, April 8, 2011

5. Friday, April 8, 2011

6. Milkyway iOS
• Run 1 of 5 (sort of) fake workunits 1000x
smaller than normal
• 10s desktop test takes 20 minutes, 8%
battery
• E-mails me the results at
milkyway4ios@gmail.com
• 143 people sent results, some many
Friday, April 8, 2011

7. Milkyway4iOS
• Get it from Peter’s Cydia repository
• “I haven’t looked at the Milkyway yet, cause
that just came out”
• “Milkyway! What is it? What can I do with it?”
• “I don’t even know what this is for? Hope it
helped you, and please update mobile notifier!
So much potential for the best notification
system!!”
Friday, April 8, 2011

8. What I’m doing
• Last presentation I forgot to mention my
main goal for the semester
• (Still haven’t started that though, so it
doesn’t matter)
Friday, April 8, 2011

9. CAL++
• Finally as fast (for the main part anyway)
• Apparently I was as fast for a long time and
I’m just dumb
• (Well actually likelihood not done + other
stuff, so a couple of extra seconds at the
end)
• Need something besides a 5870 to test it
Friday, April 8, 2011

10. I broke the server
• All I wanted was a few minor scheduler
fixes
• Now running SVN trunk server and
everything is at least partially broken
• Slowly getting better
Friday, April 8, 2011

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13. Lua
• Arbitrary initial distributions
• Less gross other configuration
• Better N-body tests
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15. GPU N-body
• O (n log n) N-body much harder than the
canonical GPU programming example
• Useless papers with no code (why are
these publishable exactly?)
• Found a starting point
Friday, April 8, 2011

16. Questions?
• milkyway.cs.rpi.edu
• https://github.com/Milkyway-at-home/
milkywayathome_client
Friday, April 8, 2011