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Let's Build a 28-Core Raspberry Pi Cluster

ikarus.sg

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

#111

Post by mciancia »

ikaruswill wrote: post #45
throwawaynothx wrote: post #34

Personally I would not use pi's for this. Massive waste of money, the experience is worth it but other than that..

What would you use then?

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.

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

#112

Post by justanother »

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'm operating an 8xPi4/8GB cluster here, the 8GB Pi4s make this a bit more interesting, but my use case is this: I use Wireguard to backhaul an AWS EIP address, and use k8s to manage instances of various small services (gitlab, websites, wordpress+web application firewall, etc), simulate AWS Lambda, and just generally have fun. But to your point: No, it certainly isn't something I undertook with pure practicality in mind.

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

#114

Post by daneel_w »

giancarlostoro wrote: post #109
_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

I'm more impressed he got trips, that's pretty amusing about the USB being as fast as an SSD. Technically SSD's are supposed to be based off SD card tech if I'm not mistaken, issue with a USB being based off the same tech is the USB speeds themselves vs a SSD can go significantly faster due to its connector (SATA or otherwise). Although I can see USB C being 'fast enough' instead.

SSDs indeed use more or less the same type of flash memory as USB sticks and SD cards, but the fundamental difference lies in how the controllers interface with that memory. While modern high-end USB memory sticks and SD cards are able to keep a sustained single write operation going at pretty high speeds, each write operation must be finalized with an update to the media's block allocation map, which is the point where the media experiences a form of throttling. Consequently this results in multiple small write operations - each of which need the same finalization procedure - bringing the performance of the stick/card to a complete crawl, with even read operations being blocked.

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

#115

Post by swebs »

_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/

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

#116

Post by giancarlostoro »

Hamuko wrote: post #110
giancarlostoro wrote: post #109

Earlier quoted context omitted.

I'm more impressed he got trips, that's pretty amusing about the USB being as fast as an SSD. Technically SSD's are supposed to be based off SD card tech if I'm not mistaken, issue with a USB being based off the same tech is the USB speeds themselves vs a SSD can go significantly faster due to its connector (SATA or otherwise). Although I can see USB C being 'fast enough' instead.

> I'm more impressed he got trips There's probably admin tools for that.

I wondered about this, but sometimes people say it cause the previous post they see is 999 so they post it, sometimes you get lucky as heck haha. I doubt they'd screw with the admin tools just to do it.

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

#117

Post by cptskippy »

> 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.

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

#119

Post by adsjhdashkj »

mciancia wrote: post #111
ikaruswill wrote: post #45

Earlier quoted context omitted.

What would you use then?

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 projects i'm working on. I expect them to be slow, low bandwidth, but simple over wifi/etc. I don't want to pay more than i need for closet computers, though, so i'm interested. :)

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

#120

Post by alibarber »

I wonder if there is something to be said for not using Ethernet in something like this? Perhaps it is possible to make a kind of IP over GPIO interface, or attach them all directly to a USB bus? It just seems to me like RasPi -> USB -> Ethernet (for less than 1m) -> USB -> RasPi has a layer or two more than necessary (and I believe the on-board ethernets on RasPi are USB interfaces to the chip too). Could be an interesting project...
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