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Let's Build a 28-Core Raspberry Pi Cluster

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Re: Let's Build a 28-Core Raspberry Pi Cluster

#131

Post by mciancia »

adsjhdashkj wrote: post #119
mciancia wrote: post #111

Earlier quoted context omitted.

I used 3 dells 9020m 3x quad core i5, 3x 16GB of ram, 2x128+1x256 ssd. All in that was around 450 eur over a year ago, all bought in EU. All three running linux with no load consume around 30W.

450eur total, or 450 a piece? I think the author mentioned only spending $449.73USD (i can't verify because the sites down) , which seems cheaper than what you mentioned. I'm also struggling to find exactly what you're talking about. I'm seeing 9020's, but no M, do they actively sell it still? I'm not nitpicking your comment - i too am interested in throwing a couple Pis in a closet for some distributed systems proje…

~450 eur in total, I bought all of them used. But most of the price came from maxed out ram and quad core cpus.

For something cheaper, I can find in my country lenovo tiny m72, for something like 40 eur. No SSD/Ram, you can configure it as you wish (and still will be cheaper then RPi, even after adding like 2GB of ddr3 - it's something like 4EUR per stick, there are 2 slots in each machine).

That is with Intel Core i3-2120T, so would expect much more performance then even RPi4

Edit: I see now that the same seller has them for ~72eur with 120GB of ssd and 4GB of ram if someone wants something ready to use.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#132

Post by cptskippy »

rtkwe wrote: post #126
cptskippy wrote: post #117

> The maximum number of ports on a consumer-grade network switch was 8, enough for 7 nodes and a cable to the router. Are there laws in Singapore that delineate between consumer and business grade networking equipment based on port numbers or something? Here in Yankey Land you can pickup a consumer grade 16-port unmanaged gigabit switch for $50 at the local Wally World. The going rate on switch ports is $3-4 per port…

It looks like it was more a question of price in their market. In the post he mentions a 16 port switch but it's 10x the price of an 8 port. I bet it's a question of there being fewer people in the Singapore market looking for an >8 port switch on the low end of the market.

The switches he references in his post are from two entirely different product verticals. One is from the unmanaged vertical, the other is from the managed PoE vertical. Not only is he ignoring that a 16 port switch exists in the unmanaged vertical, he's ignored an entire vertical of managed switches without PoE.

TP-Link makes a $40 unmanaged 16-port gigabit switch and a $80 managed 16-port gigabit switch.

He's created a False dilemma/dichotomy by pretending that other options don't exist. This is like saying "I'd like a Toyota automobile larger than the Yaris but I can't afford the Lexus LS".

Re: Let's Build a 28-Core Raspberry Pi Cluster

#133

Post by icedchai »

ArchD wrote: post #40

What's the actual use case for rpi clusters like this? If the goal is to learn docker or k8s using a realistic setup involving multiple machines, can't it be achieved by using multiple VMs on one physical desktop instead of using the cluster? The 7-node cluster has only 7GB RAM in total, which is not too much to ask on a desktop. I don't know what people do with rpi clusters and I'm honestly puzzled why people bother…

I built a cluster similar to this a while back. I am using Rock64 boards instead of Raspberry Pis. Each has 4 gigs RAM, 4 cores. It also support USB3 and I am using a USB3->SATA adapters to attach an external SSD to each.

I could've done this with VMs (and did before.) It is more of a science project to learn kubernetes, etc.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#134

Post by wy35 »

beachy wrote: post #8

I have to admire someone who spends their first paycheck on a pi cluster: > The total damage my wallet sustained from Kraken was S$626.63 or in $449.73 USD, which was virtually all I had left for the month after subtracting expenses and education loan repayments.

This is the part of the article that stood out to me most.

I definitely don't have the confidence to spend my entire paycheck on a just-for-fun project, especially considering how many projects I planned on starting but never did. Kudos on the author for being this confident and actually going through with everything.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#135

Post by swebs »

swebs wrote: post #115
_v7gu wrote: post #66

Reminds me of moot "revealing" the "datacenter" that hosted 4chan: https://imgur.com/sBLRuZY I'm putting the air-quotes because I still sincerely hope that it was a joke

Heh, it can get worse. >Wiichan it's hosted on a real Wii and it's served throught a shitty Mexican ISP. https://no.wiichan.uwu.mx/

And photos of the lovely server

https://no.wiichan.uwu.mx/meta/res/51.html

Re: Let's Build a 28-Core Raspberry Pi Cluster

#136

Post by [deleted] »

jng wrote: post #75
numpad0 wrote: post #37

Earlier quoted context omitted.

People who complain about SD card "reliability" is just writing to it way too often . Longevity of NAND flash is measured in TBW(total bytes written, in terabytes) but they have 4MB or so minimum size for write access, so people easily end up writing effectively gigabytes over weeks or months thinking it's just kilobytes averaged and use up all its life in just few months to years. You don't need "better quality SD c…

That's very interesting and explains a number of things. 4MB writes seems pretty high though as a minimum write block size, I've googled but can't find details among the sea of pages trying to sell me SD cards, won't you by chance have a reference? Thanks!

[deleted]

Re: Let's Build a 28-Core Raspberry Pi Cluster

#137

Post by alias_neo »

swebs wrote: post #135
swebs wrote: post #115

Earlier quoted context omitted.

Heh, it can get worse. >Wiichan it's hosted on a real Wii and it's served throught a shitty Mexican ISP. https://no.wiichan.uwu.mx/

And photos of the lovely server https://no.wiichan.uwu.mx/meta/res/51.html

How did that load so fast??

Re: Let's Build a 28-Core Raspberry Pi Cluster

#139

Post by noir_lord »

fock wrote: post #99
noir_lord wrote: post #87

Earlier quoted context omitted.

They built a multi-thousand pi cluster to test the SMP and configuration stuff before running it on a super computer. Virtualising thousands of CPUs on a single machine is still not trivial. Never mind simulating real world network issues. https://www.bitscope.com/blog/FM/?p=GF19A

yes, if you want to optimize a worst-case MPI-cluster, then a Pi (4) might be optimal for you (because sadly, 4 measly ARM cores with 100MBit/s is a some magnitudes removed from 100 cores and 100GBit/s Infiniband). But then you can also use a stack of old desktops, which is cheaper and you can just throw in a standard image and everything (including CUDA and MKL) can work.

> But then you can also use a stack of old desktops, which is cheaper

If electricity and cooling is free.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#140

Post by rasz »

sgerenser wrote: post #100
rasz wrote: post #73

Earlier quoted context omitted.

Imagine clustering 7 desktops from 2006, same performance.

I think the Pi4 would be closer to a 2006 desktop (Core 2 Duo). Pi3 is more like a 2002 or so Desktop, perhaps.

Oh, I didnt even realize it wasnt 4. 4 is on par with 2005 Athlon 64 X2, 3 will be ~half that, somewhere around 2003 Athlon 64.
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