Go to advanced search

by dickon
Sat Dec 04, 2021 5:49 pm
Forum: Advanced users
Topic: Moving Linux Kernel to 5.15
Replies: 101
Views: 7691

Re: Moving Linux Kernel to 5.15

I've updated my Frankenstein setup to something more vanilla PiOS64, and bumped the kernel to the latest 5.15.5-v8+ #1491. With fkms, the thing seems to hang. With no *kms overlay, it boots fine and X appears as usual. With kms, X fails to start, and the boot sequence hangs for 2-3 minutes before ss...
by dickon
Thu Dec 02, 2021 7:49 am
Forum: Advanced users
Topic: Does Anyone Have any Compiling Tips
Replies: 20
Views: 705

Re: Does Anyone Have any Compiling Tips

I wouldn't consider swap as RAM. I would: it's just very slow RAM[0]. I wouldn't. But each to his own. OK, for the avoidance of doubt: I consider swap to be RAM *in the context of any given process*, which is what we were talking about. It isn't from a hardware perspective, or even a kernel. Happie...
by dickon
Wed Dec 01, 2021 8:36 pm
Forum: Advanced users
Topic: Does Anyone Have any Compiling Tips
Replies: 20
Views: 705

Re: Does Anyone Have any Compiling Tips

I wouldn't consider swap as RAM. I would: it's just very slow RAM[0]. And if something is failing with 'out of memory', it means that the brk(2) / sbrk(2) syscall has failed, and with '11GB' of available 'RAM', that means address space exhaustion. The relevant part of the article I linked: ..."...
by dickon
Wed Dec 01, 2021 7:38 pm
Forum: Advanced users
Topic: Does Anyone Have any Compiling Tips
Replies: 20
Views: 705

Re: Does Anyone Have any Compiling Tips

I've not run a 32b kernel in a long, long time, so I may be wrong, but IIRC 32b processes on a 32b kernel are limited to either 2GB or 3GB of RAM, depending on kernel compilation options. A Pi 3B+ only has 1GB of RAM. Same as on my Pi 3B (non-plus). True, but not relevant. OP had '11GB' of RAM (1GB...
by dickon
Wed Dec 01, 2021 4:01 pm
Forum: Advanced users
Topic: Does Anyone Have any Compiling Tips
Replies: 20
Views: 705

Re: Does Anyone Have any Compiling Tips

As with i686 (and friends) and amd64, you can run aarch32 programs under an aarch64 kernel. As that's a one-line change to config.txt -- uncomment 'arm_64bit=1' and reboot -- it's worth a try. It may not help if the compile requires more than even a 64b kernel can provide to a 32b process -- in whic...
by dickon
Wed Dec 01, 2021 9:03 am
Forum: Advanced users
Topic: Does Anyone Have any Compiling Tips
Replies: 20
Views: 705

Re: Does Anyone Have any Compiling Tips

I've not run a 32b kernel in a long, long time, so I may be wrong, but IIRC 32b processes on a 32b kernel are limited to either 2GB or 3GB of RAM, depending on kernel compilation options. 32b processes on a 64b kernel I believe get closer to 4GB of RAM. Try again under a 64b kernel; it may get furth...
by dickon
Tue Nov 30, 2021 3:20 pm
Forum: Raspberry Pi OS
Topic: wap issue
Replies: 4
Views: 175

Re: wap issue

Running something on a 3B+ which claims to be debian_version 10.10: root@tempap:~# iw dev wlan0 station dump Station 50:76:af:2b:9a:21 (on wlan0) inactive time: 0 ms rx bytes: 1573553359 rx packets: 3149866 tx bytes: 3004286003 tx packets: 13903955 tx failed: 2450 signal: -74 [-74] dBm tx bitrate: 1...
by dickon
Tue Nov 30, 2021 9:27 am
Forum: General discussion
Topic: the bluetooth of pi is such a pain
Replies: 2
Views: 164

Re: the bluetooth of pi is such a pain

Douglas6 wrote:
Mon Nov 29, 2021 10:54 pm
Put PulseAudio back. Bluetooth streaming won't work without it.
That's not true. I drive mine via alsa quite happily -- I loathe PulseAudio and blow it away whenever I see it.

That said, if this 'audio menu' is expecting Pulse, then no, it won't work with alsa...
by dickon
Mon Nov 29, 2021 4:19 pm
Forum: Raspberry Pi OS
Topic: wap issue
Replies: 4
Views: 175

Re: wap issue

Odd. Seems to be fine on my Buster AP.

What does

Code: Select all

iw dev wlan0 station dump
give you for the signal strength?
by dickon
Sat Nov 27, 2021 6:46 pm
Forum: Advanced users
Topic: Moving Linux Kernel to 5.15
Replies: 101
Views: 7691

Re: Moving Linux Kernel to 5.15

Sounds identical to what I had. 4kp60 monitor, not TV.
by dickon
Tue Nov 23, 2021 6:13 pm
Forum: General discussion
Topic: Linux vs Windows
Replies: 116
Views: 3771

Re: Linux vs Windows

That's why, for quite a number of years in my COBOL experience, I would routinely get a pseudoassembler listing from the compiler. I could read the pseudoassembly code to verify that the program was going to do what I thought it and what I intended at times when I wasn't sure that COBOL would actua...
by dickon
Tue Nov 23, 2021 2:07 pm
Forum: General discussion
Topic: Linux vs Windows
Replies: 116
Views: 3771

Re: Linux vs Windows

That's C++. Which may well be entirely different to the system libm maths library. this topic is about Linux vs Windows, not about C vs C++. So the teaching resources to either PL may differ. In the context of manpages, it matters. 'man pow' will get you the manpage in section 3 -- libc and friends...
by dickon
Tue Nov 23, 2021 1:58 pm
Forum: General discussion
Topic: Linux vs Windows
Replies: 116
Views: 3771

Re: Linux vs Windows

yes, that's more elaborated and detailed, but I consider it as a little overexaggerated: which beginner needs it actually? As has been pointed out, beginners have a tendency to not be beginners for long. Languages have been written -- I'm looking at you, PHP -- which have had the unfortunate idea t...
by dickon
Tue Nov 23, 2021 10:55 am
Forum: General discussion
Topic: Linux vs Windows
Replies: 116
Views: 3771

Re: Linux vs Windows

and I was afraid that this topic will just be Platform War II Unix, and Linux specificially, won. Other than on the desktop, it's utterly dominant everywhere: every mobile phone on the planet runs either Android (Linux) or iOS (a *BSD-derived Unix). Non-Windows-network-serving servers are mostly Li...
by dickon
Mon Nov 22, 2021 4:23 pm
Forum: General discussion
Topic: Linux vs Windows
Replies: 116
Views: 3771

Re: Linux vs Windows

No way does gcc compete with Clang, let alone the paid-for toolsets. I asked the guy who develops the Circle bare metal system to try Clang and he got an immediate >5% improvement. If that's the case, he should probably stick some critical sections through the various options at https://godbolt.org...
by dickon
Sat Nov 20, 2021 7:23 pm
Forum: General discussion
Topic: Apple TV 3 Power Supply for RaspberryPi4/CM4
Replies: 13
Views: 502

Re: Apple TV 3 Power Supply for RaspberryPi4/CM4

W. H. Heydt wrote:
Sat Nov 20, 2021 6:16 pm
The fundamental point is that there is no way to get 15W from a 6W PSU.
Well, ish... There often is, just not for long before the magic smoke leaks...
by dickon
Wed Nov 17, 2021 5:14 pm
Forum: General discussion
Topic: Expectations of the Pi versions.
Replies: 64
Views: 2354

Re: Expectations of the Pi versions.

cleverca22 wrote:
Wed Nov 17, 2021 5:02 pm
viewtopic.php?t=315415&hilit=ecc
Ta. I entirely missed that discussion, and had no idea they were doing that. Interesting.
by dickon
Wed Nov 17, 2021 5:00 pm
Forum: General discussion
Topic: Expectations of the Pi versions.
Replies: 64
Views: 2354

Re: Expectations of the Pi versions.

cleverca22 wrote:
Wed Nov 17, 2021 4:52 pm
i believe there was a thread on the forum earlier, about how the pi4 has ecc ram that reports itself as non-ecc ram
I'd love to see a source for that.
by dickon
Tue Nov 16, 2021 6:06 pm
Forum: Advanced users
Topic: Funnel traffic from local devices through a remote proxy server
Replies: 2
Views: 146

Re: Funnel traffic from local devices through a remote proxy server

You could intercept all port 80 traffic from the afflicted devices with iptables, and DNAT to (eg.) squid in transproxy mode, then forward those requests on to another proxy in a chain, but this is generally messy and not ideal. It also shouldn't work for https without a lot of breaking things, and ...
by dickon
Mon Nov 15, 2021 10:00 am
Forum: General discussion
Topic: How can I check fully a device by reading every single file?
Replies: 3
Views: 183

Re: How can I check fully a device by reading every single file?

You can't -- ext4 doesn't have any form of checksumming of the underlying data, so it has no way of knowing if what it has read from the media is valid or junk. That said, the uSD card might be able to tell if a block is bad, in which case a full surface scan using badblocks or even a simple dd migh...
by dickon
Sun Nov 14, 2021 3:59 pm
Forum: General discussion
Topic: Expectations of the Pi versions.
Replies: 64
Views: 2354

Re: Expectations of the Pi versions.

I have Pico's, Zero's and Pi4's. As a hobbyist I can't see the other models being of use to me unless I got them exceedingly cheap secondhand and even then they would probably just collect dust. I believe the older models are still obtainable (chip shortages permitting, anyway) to satisfy the indus...
by dickon
Sun Nov 14, 2021 3:55 pm
Forum: General discussion
Topic: Expectations of the Pi versions.
Replies: 64
Views: 2354

Re: Expectations of the Pi versions.

There are a few posts of complaints though, which kind of got me thinking, top of the list is what did you expect for the specs and price point?? When the original Pi1B was released in 2012, the price/performance was nothing short of astonishing. It was a truly ground-breaking product, the likes of...
by dickon
Thu Nov 11, 2021 4:41 pm
Forum: General discussion
Topic: RPI using another RPI as relay and WiFi router
Replies: 13
Views: 406

Re: RPI using another RPI as relay and WiFi router

OK, ideally, you shouldn't need to access anything on B - it doesn't actually have to have an IP address in order to pass packets between its interfaces. If you did statically assign an address on A, and you've done the same on your laptop's wifi interface -- don't aske me how; I don't do Windows --...
by dickon
Wed Nov 10, 2021 9:58 pm
Forum: General discussion
Topic: Interesting use for 450 raspberry pi's!
Replies: 25
Views: 1128

Re: Interesting use for 450 raspberry pi's!

Very possibly. 3KW over 450 Pi works out at 6.666W (recurring) per Pi. Or, by my back of the envelope calculation roughly 2/3 of the power drawn by a 4B under full load (9W. 1.8A * 5v). I find it unlikely that a 4B drawing 9W will throw away more than 2/3 of it as waste heat. I doubt any reasonably...
by dickon
Wed Nov 10, 2021 9:46 pm
Forum: General discussion
Topic: RPI using another RPI as relay and WiFi router
Replies: 13
Views: 406

Re: RPI using another RPI as relay and WiFi router

DHCP -- google it -- is the mechanism that every OS for the past ~25 years has used to discover its network address and associated details. It requires a machine on the network to issue those addresses, and in a home setup, this is usually performed by your router. It requires some setup, and static...

Go to advanced search