Live data from Hacker News

Raspberry Pi 4

raspberrypi.org

731–740 of 859 posts

Re: Raspberry Pi 4

#731
post #715

Earlier quoted context omitted.

Can you link it? Was the video streaming or playing from disk? Perhaps it was an unsupported video codec? There are certain circumstances where the pi may struggle to play video, but I think for common formats they graphics driver has hardware level support for decoding. If the video format was weird and it had to decode with the CPU it could see problems. Another issue is the power supply. If you do not use a qualit…

https://www.theverge.com/circuitbreaker/2019/6/24/18715211/r... they write "It reportedly struggles with full screen video playback from YouTube for example, even if you turn down the resolution to 480p." I was surprised by this review too. Not sure where they get that from

"reportedly"

Ugh.

Re: Raspberry Pi 4

#732
post #658

Oh my! This is such a crazy upgrade. I've been using the RPI2 as my HTPC/NAS at my folks, and I'm so happy with it. I was itching to get the last one for myself. USB 3.0! Gigabit Ethernet! WiFi 802.11ac, BT 5.0, 4GB RAM! 4K! $55 at most?! What the!? How the??! I know I'm not maintaining decorum at Hacker News, but I am SO mighty, MIGHTY excited! I'm setting up a VPN to hook this (when I get it) to my VPS and then do…

Excited too, but $55 + $13.95 shipping = $68.95 is inching closer to the $99 (free shipping) territory of the Jetson Nano.

When you add up adapters and cables the rpi is closing in on a chromebook on sale. So not that cheap any more.

Re: Raspberry Pi 4

#733
post #479

Earlier quoted context omitted.

I can relate. However these days I have found a new life for those abandoned Pis: I install Pi-Hole [1] on them and set them up for family and close friends. [1] https://pi-hole.net/

I wish pi-hole was just a tiny bit more polished. I found it takes a lot of work (and knowledge of linux networking) to get up and running properly and stable.

A great option I've found is to use the DietPi distribution that has Pi-hole configuration/install wizard built in (https://dietpi.com)

After having various weird network issues and instability on a different OS with Pi-hole (updates often broke), I switched to DietPi, and now my PiHole and OS upgrades are extremely stable.

The DietPi installer/configuration for Pi-hole sets up all the networking for you in the install "wizard", took all the weird networking headaches out for me

Re: Raspberry Pi 4

#734
post #553

Earlier quoted context omitted.

That's silly. RasPis are stupidly useful. I've got: * A Zero W hooked up to a PM2.5 to do air quality monitoring in the house. Just bought a couple more sensors for it (VOC, eCO2, etc), but haven't hooked them up yet. * A 3B+ running the UniFi controller for my home network. * One is running a custom Hue automation I built to shift the color temperature of the lights throughout the day. * One is built into an interne…

> One is running a custom Hue automation I built to shift the color temperature of the lights throughout the day. Ooooh do you have the code up somewhere for this? I would love to set it up at home :)

Not the OP but I use Kelvin for this, works great! It basically treats my Hue White Ambience bulbs like Flux, where they automatically dim and warm in the evenings. Those changes happen gradually over the course of minutes/hours so it's not jarring.

https://github.com/stefanwichmann/kelvin

Re: Raspberry Pi 4

#735

Does anyone have a link for building a Raspberry Pi cluster over gigabit ethernet? A quick search turned up some stuff: https://medium.com/@glmdev/building-a-raspberry-pi-cluster-7... https://epcced.github.io/wee_archlet/ https://www.raspberrypi.org/magpi/cluster-computer-raspberry... Specifically, I'd like to find software that makes the cluster appear as a single memory address space and N identical CPUs/cores. Whe…

Just searched a bit more for MPI integration with various languages. I find things like this kind of heartbreaking:

https://godoc.org/github.com/cpmech/gosl/mpi

It provides MPI bindings in Go, but they really should have provided an MPI layer internally so that the Go metaphors of things like channels and goroutines "just work" with no special syntax.

I think this is where I'm getting stuck. So much cluster software provides interfaces to send/receive data and get the current thread's CPU id and total number of CPUs. But I'm not finding much info on doing this directly in the kernel or language runtime so that the client can be written in a topology-agnostic fashion.

Edit: there doesn't seem to be a Go-native MPI runtime (yet) https://groups.google.com/forum/#!topic/golang-nuts/t7Vjpfu0...

Re: Raspberry Pi 4

#736

Does anyone have a link for building a Raspberry Pi cluster over gigabit ethernet? A quick search turned up some stuff: https://medium.com/@glmdev/building-a-raspberry-pi-cluster-7... https://epcced.github.io/wee_archlet/ https://www.raspberrypi.org/magpi/cluster-computer-raspberry... Specifically, I'd like to find software that makes the cluster appear as a single memory address space and N identical CPUs/cores. Whe…

Just searched a bit more for MPI integration with various languages. I find things like this kind of heartbreaking: https://godoc.org/github.com/cpmech/gosl/mpi It provides MPI bindings in Go, but they really should have provided an MPI layer internally so that the Go metaphors of things like channels and goroutines "just work" with no special syntax. I think this is where I'm getting stuck. So much cluster software…

I believe Erlang's messaging/multithreaded primitives work over the network?

Re: Raspberry Pi 4

#737
> The power savings delivered by the smaller process geometry have allowed us to replace Cortex-A53 with the much more powerful, out-of-order, Cortex-A72 core; this can execute more instructions per clock, yielding performance increases over Raspberry Pi 3B+ of between two and four times, depending on the benchmark.

Looks like the Pi 4 will be vulnerable to Spectre. That's unfortunate, since it seems like this is quite an upgrade otherwise.

https://en.wikipedia.org/wiki/Spectre_(security_vulnerabilit...

> ARM has reported that the majority of their processors are not vulnerable, and published a list of the specific processors that are affected by the Spectre vulnerability: Cortex-R7, Cortex-R8, Cortex-A8, Cortex-A9, Cortex-A15, Cortex-A17, Cortex-A57, Cortex-A72, Cortex-A73 and ARM Cortex-A75 cores.

Re: Raspberry Pi 4

#738

Earlier quoted context omitted.

That's silly. RasPis are stupidly useful. I've got: * A Zero W hooked up to a PM2.5 to do air quality monitoring in the house. Just bought a couple more sensors for it (VOC, eCO2, etc), but haven't hooked them up yet. * A 3B+ running the UniFi controller for my home network. * One is running a custom Hue automation I built to shift the color temperature of the lights throughout the day. * One is built into an interne…

Which CO2 sensor did you go with and how happy are you with it, if you don't mind talking about it?

I'm using a co2meter.com one [1] connected with USB. Reading out the values is a bit slow, but I just do that in a cron job every 5 minutes and log the results. This does exactly what I needed it to do with a minimum of fuss, so I'm happy with it.

[1] "CO2Meter RAD-0301 Mini CO2 Monitor" on Amazon, $70

Re: Raspberry Pi 4

#739
post #737

> The power savings delivered by the smaller process geometry have allowed us to replace Cortex-A53 with the much more powerful, out-of-order, Cortex-A72 core; this can execute more instructions per clock, yielding performance increases over Raspberry Pi 3B+ of between two and four times, depending on the benchmark. Looks like the Pi 4 will be vulnerable to Spectre. That's unfortunate, since it seems like this is qui…

Yes, it probably is. But for many use cases that is totally unimportant.

Re: Raspberry Pi 4

#740
post #732
post #658

Earlier quoted context omitted.

Excited too, but $55 + $13.95 shipping = $68.95 is inching closer to the $99 (free shipping) territory of the Jetson Nano.

When you add up adapters and cables the rpi is closing in on a chromebook on sale. So not that cheap any more.

Comparing one item at list with another on sale is a bit of an apples-to-oranges comparison.
Post reply on HN