Thursday, June 20, 2019

Very Large Raspberry Pi Cluster - Part III

I spent most of today fighting with Fusion 360 so I don't have much progress to report besides a serious complaint about Fusion 360. A new updated was released. If I didn't upgrade I couldn't save. If I upgraded I lost my changes. I had no choice but to upgrade, loose my changes and redo them. Then when I loaded up my models there were errors with unresolved imported components. The error states that if I save my model in this state I will loose my model. Personally I find this unacceptable and while I like Fusion 360, I like the disruption to the CAD world, many of the features, the price is reasonable and the fact that it runs on Mac and Windows, I also find it extremely buggy and a toy. I may be switching back to SolidWorks. Hopefully I get all of this resolved in the next few days and can report on the progress.

Update: After restarting Fusion 360 five times, and reloading the model after closing it with the error saying it will be destroyed, I finally got all the linked models and everything to load. So it was just a lot of ignoring errors and closing and reopening things and much ado about nothing, but extremely worrisome that just an update being pushed could cause such concern.

Wednesday, June 12, 2019

Very Large Raspberry Pi Cluster - Part II

Last week I posted about the very very large Raspberry Pi cluster that I'm building for Code One. Read that post here.

I realized after that post went live that I didn't give any backstory as to what we are actually building. When building something like this it's easy to document the entire process, it just takes 2-3 times as long to build. I figured I'd document the process in a fast and loose to blogs, YouTube and Twitter. So, before we go any further with the status of current progress let's backup.

Last year Stephen Chin and Gerald Venzl came to me with an idea. The conversation went something like this:

Stephen: "Gerald has an idea"
Gerald: "Let's build a HUGE biggest Raspberry Pi cluster for 2019 CodeOne. Like 1000 Raspberry Pis. The developers will love it. We will call it OSCAR!"
Me: "1000 is a lot, but 1024 is a better number"
Gerald, Stephen: "😃"

Back in the lab a few months later Jasper Potts and I did some math about how to pull off a cluster like this and we produced this rendering.

There will be 49 2U racks containing 21 Raspberry Pis (last weeks post was about this).
There will be 22 network switches.
There will be 18 USB power supplies.
There will be one server.
There will be 8 fans. This thing is going to get hot.
There will be 5 six foot server racks.
It will consume 120 amps of power.
It will require a fork lift to move.
It will network boot because can you imagine flashing 1024 SD cards?
In actuality, the server running the entire thing may be more powerful than all those Pis.
All of this barely fits in 5 racks.
This will travel to other Oracle events around the world next year.

WARNING: Actual numbers may vary, but the 1024 is the goal.

Wednesday, June 5, 2019

Very Large Raspberry Pi Cluster - Part I

I am building a very large Raspberry Pi Cluster and I'm going to document the process here. My goal is to post once a week until it's complete and shows up at Oracle Code One in San Francisco  September 2019.  Thus far an unimaginable amount of work has been put into this project to determine if it's even viable. We think it's viable so I'm going to start talking about it. There may be some mistakes. No, there will be some mistakes. Hopefully I won't make too many of them.

For the first taste, here is a rendering of a 2U rack that will hold 20 Raspberry Pi Model 3B+. I've printed out about 50 versions of this and this packs the most in while still allowing heat dissipation and still being serviceable in a standard server rack.

Disclaimer: The Raspberry Pi model is one I found on the Fusion 360 store thing. The rest is rendered by my own mad modeling skills.

Now that I've modeled this up and printed it I'm going back to the drawing board. It takes 14 hours to print the orange part which holds half of the Pi rack using an Ultimaker S5 with a .08mm nozzle 10% infield and .2 layer height. The Pi snaps in nicely but there are too many issues and this part needs to be nearly perfect.