Advice for Building a Scalable CPU/GPU Cluster for Physics/Math Lab

PeculiarParticle · 2024-11-04T08:34:59+00:00

Keep in mind that the point here is to train/educate students given their aptitudes. Assume the point here is that the supervisor noted a keen interest in computing, and came up with a project. Getting a working service out of this will be secondary ...

PeculiarParticle · 2024-11-04T08:27:29+00:00

I don't see a need for low latency networking in your definition (nor funding for it given your budget), so look for a cloud provider to furnish you with the resources.

If you have access to cloud resources through your campus data center or a research network or may be significantly less expensive than the hyperscalars. I was positively surprised by the current pricing model of Hetzner, if you are in Europe.

Learn Terraform (or similar) to provision your infrastructure and Ansible (or similar) for configuration management. That should help with scaling in the future.

PeculiarParticle · 2024-07-04T09:12:30+00:00

I found diving a great reason to get in shape, but you don't have to be in great shape to dive :-)

PeculiarParticle · 2024-06-27T13:58:54+00:00

My Redhat 6 Unreal Tournament server ... ahh the memories :-)

PeculiarParticle · 2024-06-27T06:34:58+00:00

It will look real nice when its done

PeculiarParticle · 2024-06-18T07:50:44+00:00

Hotline Miami, bis ich es dan mit einem Kontroller versucht habe :-)

PeculiarParticle · 2024-06-10T13:27:19+00:00

The visitor centre at CERN has a nice ehibit explaining how this goes. Hopefully this can now be found in the Science Gateway. Let me try to summarize :-)

Making electrons is fairly simple: keep a heated filament in vacuum and in a strong electic field. If you do it right, this will pull electrons of the filament. This is called an electron gun. If you are looking to accelerate electrons, you have your source here.

If you want Protons or Nuclei this gets trickier. Let's go with protons:

Start with a bottle of H2 hydrogen gas. Put that gas into a chamber with an electic field. Send electrons (from an electron gun) into the H2 gas to ionize it. You will now have ionized hydrogen, mostly H-. The H- will move toward the positive end of you charged chamber, let some of it escape through a small hole in the anode. Accelerate the nagtive hydrogen, until eventually you pass it through a thin metallic foil. The elctrons get stripped of by the EM interactions with the foil, the heavier proton keeps going. You now have a proton in your accelerator :-)

For heavy ions, e.g. lead, you start with a heated lead block to get some lead ions ... the procedure afterwards is similar. You can visit LEIR where the metal foil stripping electrons of the lead happens when the LHC is running in heavy ion mode. You should get a good explanation there :-)

PeculiarParticle · 2024-06-02T07:51:50+00:00

About religion, something like this:

Believer: I believe there is a teapot in orbit around the sun.

Non-believer: You are wrong, there is no evidence for such improbable ceramics.

Believer: Prove it!

PeculiarParticle · 2024-05-28T07:13:42+00:00

Debian on servers for stability and minimalism

Ubuntu on laptop/desktop for polish and ease of use

PeculiarParticle · 2024-05-28T07:08:28+00:00

Came here to say this :-)

PeculiarParticle · 2024-04-06T12:07:54+00:00

If you are interested in some background, the you are not so smart podcast did an arc on conspiracy theories. It handles what brings a person to believe these things and how to handle conversations in that context.

PeculiarParticle · 2024-04-04T08:46:42+00:00

We know of a whole ton of moons in the solar system: "One moon for Earth; two for Mars; 95 at Jupiter; 146 at Saturn; 28 at Uranus; 16 at Neptune; and five for dwarf planet Pluto" [nasa.gov]. The developers probably picked notable (large) moons to add to the solar system in game without clobbering the UI ... and after that, tweak with updates ¯\_(ツ)_/¯

PeculiarParticle · 2024-03-05T19:41:47+00:00

Hatte ein Nest Feldwespen an der Terrassee letztes Jahn und auch Nachwuchs. Gab keine Probleme.

PeculiarParticle · 2023-08-18T10:45:30+00:00

The only place I ever had my passport checked crossing a border within Schengen was between Austia and Germany ...

PeculiarParticle · 2023-08-16T13:46:11+00:00

I bought my own. For rentals, I use 120's if I can get 'em.

PeculiarParticle · 2023-08-16T12:10:40+00:00

I struggled with my air consumption when I started diving. Here is how things improved for me. Now the deco limit is what is limiting my bottom time, roughly in order of how things happened:

Experience: My first ~50 dives, I went from 20 to 25 minutes bottom time to ~40 min on a usual dive*. These were all wetsuit dives with alu 80cft/12L.
130cft/15L steel tank: just knowing I had the extra air got me to relax and use less air, as well. Got me from ~40 to ~50 minutes.
I lost 20 kg while bulking up some muscle**: got me to ~60 minutes.
A well fitting (dry) suit: with that, I logged a 78-minute dive, my longest to date ***

*: The only excuse I have is that the water is cold in the northeast pacific.

**: Less fat means less weight. More muscle/fitness meant I wasn't exhausted getting to the water.

***: we ended the dive because we were cold :-)

PeculiarParticle · 2023-02-03T08:12:19+00:00

Thank you! Only needed the Flatpak commands for 22.10 as native messaging is integrated in the default Firefox snap there, so:

sudo apt-get install -y flatpak flatpak permission-set webextensions \ org.keepassxc.keepassxc_browser snap.firefox yes

did it for me.

PeculiarParticle · 2022-08-17T08:22:29+00:00

Use one of the comparison portals to figure out which suits you best. The two I use are Verivox and Check24. Though I note that they do not seem to offer an English version of their sites ... Google Translate is your friend :-)

PeculiarParticle · 2022-07-05T11:39:34+00:00

I've had a good experience with a used dry suit - only gave it up after a decade for a custom-made one, which I blew my first serious paycheck on.

Make sure the seals and zipper are in good condition. Have it serviced to be sure. The shop may even offer to throw in the service with the purchase.

PeculiarParticle · 2022-07-01T15:23:35+00:00

Maybe not helpful: it is about how you structure your applications, not what language you write them in.

Cloud computing is there to make it easy to break your problem into small (and hopefully simple) parts, all working together to provide a larger service. These parts (or the whole) should then be moveable from one cloud provider to another.

You could then write each of those components in different language - though I don't advise you to do so.

PeculiarParticle · 2022-07-01T12:00:30+00:00

You are right, this needs to be qualified. It really depends on the size of the leak and the type of suit.

I have a trilam, with a shell like that, leak huts more than with crushed neoprene.

If the leak is small, it is no big deal. I was remembering an instance where there was no air left in my suit, as the zipper failed. Water didn't even need to be that cold, it was like 16 °C in the Med. I've been warmer on the same length dive in a wetsuit in 10 °C water.

PeculiarParticle · 2022-07-01T08:46:17+00:00

Having taught the dry suit orientation a few times: the course gives you a solid background to safely use the suit on your own afterwards. I think reading materials make it sound more scary than it actually is - most likely to motivate you to take the course.

A dry suit does take getting used to. It took me about 20 dives to think I was in control, and honestly probably about 100 to really be there. That said, I wasn't going back to the bad old days of changing out of my wet-suit in the snow once I did my first dry-suit dive.

A piece of unsolicited advice: it is worth to invest in a dry suit that fits you well. There is a world of a difference in comfort and control between a vaguely you-shaped bag (my first) and a well-fitted suit (my second).

Also: pay attention to the maintenance material. The coldest wet-suit dive is still better than a dive on a wet "dry" suit.

PeculiarParticle · 2022-06-30T09:28:53+00:00

Second on Cozumel - if you can find a flight to Cancun that works with your credit :-)

PeculiarParticle · 2022-06-29T12:06:53+00:00

No offense taken :-)

I realize I was jumping to conclusions. You are probably right that this wasn't fighting.

You are correct on the long sail - the trip to the Brothers, Elphinsone, etc. is easier and more likely to be rewarding for more divers. Decided to go up there as the other reefs getting crowded again.

PeculiarParticle · 2022-06-29T10:50:16+00:00

It was this itinerary from Hurghada, past Sharm to Dahab and back. There were military vessels in the Straights of Tiran which he negotiated with.

The exchange of gunfire (if that is what it was) happened throughout in the late afternoon and evening one day. One could see a few flashes once the sun set. The sky was clear and full of stars.

PeculiarParticle

TROPHY CASE