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Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

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Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#61

Post by willis936 »

echlebek wrote: post #60
willis936 wrote: post #24

Earlier quoted context omitted.

In terms of computer per dollar yes. In terms of compute per joule, no.

I don't think that's true either. You can get 8-core desktop Ryzen parts that have a TDP of 65 watts. I have a passively cooled 8-core Ryzen system that uses a 240 watt power supply. Also: by the time you've wired up 8 raspis you end up using quite a bit of power just to connect them all together with a switch. Raspberry Pi 4s need a maximum of 15 watts each. So 120 watts just for the computers. Even if you discount…

You're calculating the raspi 4 power consumption based off of recommended USB power supply current rating. The actual expected load power consumption without peripherals is 1/5 to 1/3 of that (3-5 W rather than 15 W).

https://www.raspberrypi.org/documentation/hardware/raspberry...

https://www.pidramble.com/wiki/benchmarks/power-consumption

https://raspi.tv/2019/how-much-power-does-the-pi4b-use-power...

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#62

Post by 908B64B197 »

His workload is embarrassingly parallel[0] and the message-passing between the Pi is basically free since the results are so small to send-back (and there's nothing to send to each node on startup). He's effectively doing a trivial map-reduce [1].

He could probably get even better than the Pi cluster by using a (single) GPU.

[0] https://en.wikipedia.org/wiki/Embarrassingly_parallel

[1] https://en.wikipedia.org/wiki/MapReduce

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#63

Post by hutrdvnj »

waterhouse wrote: post #58
hutrdvnj wrote: post #49

Earlier quoted context omitted.

Don't know why I'm getting down voted, but thanks, that's exactly what I was looking for.

I suspect because the author of the blogpost probably doesn't own an M1 Mac (he mentions benchmarking several machines and it seems unlikely he would have forgotten the M1 if he had one), so your comment (interpreted as a request to the author) amounts to "Please spend about $1000 on another computer because I want another benchmark result", not to mention shipping time would make it days before he could report back.…

Ah okay, I didn't want the author to spend $1000, I just wanted someone with a M1 like wil421 to redo the benchmark.

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#64

Post by m463 »

m463 wrote: post #8

I tried FindingPrimesMulti.py on a 3970x: Find all primes up to: 10000 using 256 processes. Time elasped: 0.51 seconds Number of primes found 1229 Find all primes up to: 100000 using 256 processes. Time elasped: 36.71 seconds Number of primes found 9592 Find all primes up to: 200000 using 256 processes. Time elasped: 149.55 seconds Number of primes found 17984 EDIT: ran it again: Find all primes up to: 200000 using 2…

sorry, was using python2 - using: python3 ./FindingPrimesMulti.py

  Find all primes up to: 10000 using 256 processes.
  Time elasped: 0.36 seconds
  Number of primes found 1229

  Find all primes up to: 100000 using 256 processes.
  Time elasped: 15.7 seconds
  Number of primes found 9592

  Find all primes up to: 200000 using 256 processes.
  Time elasped: 58.07 seconds
  Number of primes found 17984
(this was debian 10)

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#65

Post by ThrowawayR2 »

artiscode wrote: post #15

I would really like to see how a raspi cluster fares with "real world" loads, like running an app or a distributed system, instead of calculating pi. I'm genuinely curious whether there would be any gains by running Docker containers, each on a separate Raspberry Pi. I personally am a web developer, therefore my technology stack is almost always the same - an app server, a background worker, a queue and a database. O…

There's the Geekbench 5 measurements:

Apple M1: https://browser.geekbench.com/v5/cpu/search?utf8=%E2%9C%93&q...

Raspberry Pi 4: https://browser.geekbench.com/v5/cpu/search?utf8=%E2%9C%93&q...

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#66

Post by m463 »

neatze wrote: post #12
m463 wrote: post #10

Earlier quoted context omitted.

is this what you mean? FindingPrimesMulti-1.zip

If you have mpi4py then I would try this one: https://github.com/joshjerred/mpi4py-with-multiprocessing-Ch... To me this would be more fair comparison between single cpu and pi cluster.

apt-get mpi4py3 and using python3 primeMP.py is lots faster

  Find all primes up to: 10000
  Nodes: 1
  Time elasped: 0.12 seconds
  [1229]
  Primes discovered: 1229

  Find all primes up to: 100000
  Nodes: 1
  Time elasped: 4.52 seconds
  [9592]
  Primes discovered: 9592

  Find all primes up to: 200000
  Nodes: 1
  Time elasped: 17.43 seconds
  [17984]
  Primes discovered: 17984
I even tried:

  Find all primes up to: 1000000
  Nodes: 1
  Time elasped: 383.2 seconds
  [78498]
  Primes discovered: 78498

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#67

Post by neatze »

m463 wrote: post #66
neatze wrote: post #12

Earlier quoted context omitted.

If you have mpi4py then I would try this one: https://github.com/joshjerred/mpi4py-with-multiprocessing-Ch... To me this would be more fair comparison between single cpu and pi cluster.

apt-get mpi4py3 and using python3 primeMP.py is lots faster Find all primes up to: 10000 Nodes: 1 Time elasped: 0.12 seconds [1229] Primes discovered: 1229 Find all primes up to: 100000 Nodes: 1 Time elasped: 4.52 seconds [9592] Primes discovered: 9592 Find all primes up to: 200000 Nodes: 1 Time elasped: 17.43 seconds [17984] Primes discovered: 17984 I even tried: Find all primes up to: 1000000 Nodes: 1 Time elasped:…

that's makes much more sense :)

I found this: https://setiathome.berkeley.edu/cpu_list.php

ARMv7 looks like is raspberry pi, looking at this I can't see any computational value for such cluster setup.

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#68

Post by bogwog »

thraway123412 wrote: post #59
bogwog wrote: post #47

Earlier quoted context omitted.

Would it though? The cluster has more cores (each PI4 has a quad core), so for certain workloads it seems like it could realistically beat a single 8-core with higher clocks. As always, a benchmark is the only thing that will prove it.

It absolutely would. These cores are in a completely different class. If you care about benchmarks, a Pi4 will score around 200 points (1 core) or 550 points (4 core) at 1.5GHz on GB5. At 2GHz you can reach around 700 points multi-core. Ryzen 2700 will easily go above 6000 points in multi-core bench without overclocking. So even in a theoretical, embarrasingly parallel workload with minimal sharing between cluster no…

Where are you getting these "points" from? Without a real world benchmark I don't see why you're so confident about this.

The video in the OP showed 8 pis, and assuming 4 cores each that's 32 cores total.

A raytracing benchmark would be interesting because you could divide the work up-front and not have to worry about communication between nodes in the cluster, and each node doesn't need that much memory.

Maybe the ryzen 2700 beats the 8 PI cluster, but clearly there's an X number of PIs that will beat the ryzen. Maybe it's X = 10 PIs, or 20, or 200? Idk, but it could also just be 8. There's no way to know for sure without a benchmark.

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#69

Post by canadianfella »

jamesbfb wrote: post #36
thraway123412 wrote: post #34

Earlier quoted context omitted.

Well, he also needed to add a cooler and a bunch of tubes & eight mounts to get coolant running on each Pi, eight ethernet cables, eight power cables, a power supply with enough outputs, a 16-port ethernet switch, and (correct me if I'm wrong) eight SD cards, if only to store a bootloader that can do pxe. So eight Pies alone do not make a complete cluster, just as one Ryzen alone does not make a complete computer. A…

Jeff Geerling did a blog post[0] and video (series) on this very thing a while ago that goes into some of the hardware and costs. Whilst the costs can be negligible, it looks like a hella lot of fun! [0] https://www.jeffgeerling.com/blog/2020/raspberry-pi-cluster-...

Although it can be very inexpensive it can be fun?

Re: Can My Water Cooled Raspberry Pi Cluster Beat My MacBook?

#70

Post by thraway123412 »

bogwog wrote: post #68
thraway123412 wrote: post #59

Earlier quoted context omitted.

It absolutely would. These cores are in a completely different class. If you care about benchmarks, a Pi4 will score around 200 points (1 core) or 550 points (4 core) at 1.5GHz on GB5. At 2GHz you can reach around 700 points multi-core. Ryzen 2700 will easily go above 6000 points in multi-core bench without overclocking. So even in a theoretical, embarrasingly parallel workload with minimal sharing between cluster no…

Where are you getting these "points" from? Without a real world benchmark I don't see why you're so confident about this. The video in the OP showed 8 pis, and assuming 4 cores each that's 32 cores total. A raytracing benchmark would be interesting because you could divide the work up-front and not have to worry about communication between nodes in the cluster, and each node doesn't need that much memory. Maybe the r…

GB5 = Geekbench 5. It is a real world benchmark.
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