Weekend Fluff / Linux in the Wild Thread - October 25, 2019

Welcome to the weekend! This stickied thread is for you to post pictures of your ubuntu 2006 install disk, slackware floppies, on-topic memes or more.

When it's not the weekend, be sure to check out r/WildLinuxAppears or r/linuxmemes!

https://redd.it/dn0fe4
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Back from the Blender Conference 2019 - Krita Developers
https://valdyas.org/fading/hacking/krita-hacking/back-from-the-blender-conference-2019/

https://redd.it/dn0dpx
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When I start ddd on ubuntu 18.04(assembly program) it shows this and ddd doesn’t work. I’m new is SE so I don’t know what to do..
https://redd.it/dn35mm
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Many desktops? One distro?

Hi!!!
What do you think about using many different desktops in one single distribution?? Is that worth?? Or is better one per distro??
Give me all you think about it/experiences!!!
Thanks...

https://redd.it/dn5obv
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Turning your Linux server into a free* Twitch Streaming PC
https://www.reddit.com/r/homelab/comments/dmyz69/turning_your_linux_server_into_a_free_twitch/

https://redd.it/dmz4qo
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firefox reddit dark css

for those on firefox this gets rid of the dotted lines around the buttons and other mumbo jumbo stuff, plus if using nonoscript you need redditstatic.com and reddit.com js running, cookiesenabled, dom dot storage enabled, js enabled via about:configso the dropdown menus will work, this cleans the site up a bit without getting rid of the stuff ya might want to viewmod for your config a dark theme css layover that uses invert,hides ads, promoted junk, plus includes notes for what reddit js noscripts need to be allowed via nonoscript in orderto have the drop down menus work, hid the search bardrop down junk for 'trending' while letting the profile dropdown menu work, next i'll hide the bubble popups when you click something in profile, really annoying

[screenshot](https://raw.githubusercontent.com/tokzco/cssz/master/reddit.png) of the [css](https://raw.githubusercontent.com/tokzco/cssz/master/reddit.css)

https://redd.it/dn7z5w
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BiDirectional text (Arabic, Farsi, Hebrew, etc) support in console programs
https://gist.github.com/XVilka/a0e49e1c65370ba11c17

https://redd.it/dn8uka
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SOLVED : [Linux] How can I start Discord on login minimized to the tray?
https://www.reddit.com/r/discordapp/comments/ar9mbg/linux_how_can_i_start_discord_on_login_minimized/

https://redd.it/dmx7yc
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What are things you love about the Linux kernel and things that you hate about it?

See noscript.

https://redd.it/dn9rwq
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fractional scaling in linux

please list linux distros with fractional support like kde neon does.

https://redd.it/dnbt0v
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Switching to Linux after spending t+ years on Windows
https://redd.it/dnc5dv
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All the videos of talks from KDE's Akademy 2019 event are now on PeerTube
https://www.reddit.com/r/kde/comments/dncnic/all_the_videos_of_talks_from_akademy2019_are_now/

https://redd.it/dncob2
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Kritas founder on the importance of Blender and community.
https://valdyas.org/fading/hacking/krita-hacking/back-from-the-blender-conference-2019/

https://redd.it/dndo2c
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Raspberry Pi 4 Ubuntu Server / Desktop 18.04.3 Image (unofficial)
https://jamesachambers.com/raspberry-pi-4-ubuntu-server-desktop-18-04-3-image-unofficial/

https://redd.it/dnfv9b
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Grub still there.

Long story short.
I installed several linux distros for dual-booting with windows 10.
Problem: I always deleted the partition but most of the grubs are still visible in the boot menu.

https://redd.it/dng98l
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New PHP Flaw Could Let Attackers Hack Sites Running On Nginx Servers
https://thehackernews.com/2019/10/nginx-php-fpm-hacking.html

https://redd.it/dnj5da
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KeePassXC 2.5.0 released
https://keepassxc.org/blog/2019-10-26-2.5.0-released/

https://redd.it/dnmeyj
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An electrical engineers opinion on the Librem 5.

Hello everyone. In light of the most recent update, ["Supplying the Demand"](https://puri.sm/posts/supplying-the-demand/), I would like to share my **opinions** on the current state of this device.

The following is some basic info of my background. You are free to criticize any and all aspects of this post.

1. I am an electrical engineer who specializes in digital signal processing (DSP), systems (debug), and comms.
2. I currently work at a large company that operates in the cell phone industry. My roll is within a 5G research/testing department.
3. This is my main Reddit account which is reasonably old and active. I typically lurk a lot and rarely post.
4. My knowledge of programing is very limited. I preform 95% of my job functions with Python and Matlab. This will be a hardware and systems level discussion of the Librem 5.

The CEO of Purism, Mr. Todd Weaver, outlined three major problem areas within the current iteration of the Librem 5: **Thermals, Power, and Reception**. Let us go through these in order.

~~=========================================================~~

**Thermals:**

Thermals and power are closely intertwined so let's only focus on Purism's options to fix thermals, assuming they make no changes to improve power consumption. Given that the Librem 5 is (thankfully) a thick device, I see no reason why Purism would not be able to fix the thermal issues. In a worst case scenario, they would have to redo the motherboard layout, add some thermal pads/paste, and maybe add a [thin yet expensive copper vapor chamber.](https://celsiainc.com/wp-content/uploads/2018/12/advantages_of_vapor_chamber.png) This would result in a worst case scenario of a possible delay and additional bill of material cost of 20-30 dollars. *In my opinion, the thermal problems are solvable and within reach.*

**Power:**

Because of the strict requirements Purism placed on the goals of this device (regarding binary blobs), they have chosen [modem(s)](https://puri.sm/faq/supported-networks/) that were not designed for this use case. All four variants of the offered modems by both modem vendors (Gemalto and Broadmobi) are internet of things (IOT) class chips. From an EE perspective, these modems are fine **in the right context.**

Industrial communication with large equipment (shipping yards)?

Great.

Vending machine credit card processing?

Also Great.

A mobile device (UE) that users will be moving around (mobility) and expecting good reception on a strict power budget?

And thus we arrive at the root of the power and reception issues. I am going to talk about reception in it's own section so lets talk power.

The large modem vendors in the smartphone space (Qualcomm, Samsung, Huwawei/HiSillicon, MediaTek, Intel) spend an huge amount of time and effort on power management features. Not only is logic level hardware design done with power in mind, but once the chip is fully taped out, months of effort by 100's of engineers is sunk to improve power characteristics via firmware development and testing. As much as we all hate binary blobs that may (probably) spy on us, these companies have good reason to keep their firmware (and thus power saving IP) secret. Significant competitive advantages are created between the modem vendors from this firmware and digital logic level power savings effort.

When a company markets their modem as "IOT", they are effectively admitting that little to no effort was done to keep chip power in check. In the example IOT applications I mentioned (vending machine's and large industrial equipment), power does not matter. The devices themselves draw far more power than the modem that will be inside. Space is not a concern. So companies making IOT products with these modems simply ignore the power draw and slap on a large heat-sink. From lurking on r/linux and /r/Purism , I have seem others call out the modems without going in depth to why these products even exist. Yes, the specifications and capabilities of these modems are far lower. So be it. I think all of

use are fine with "100 MBit" peak down-link (reality will be 10-20). The problem is that these chips were not designed for power efficiency and never intended to be in a small compact device. You would not put the engine of a Prius into a flatbed truck. The engineers at Toyota never intended for a Prius engine to go inside such a vehicle. The same situation has happened here.

Now on to how Purism can fix this power problem. With a herculean effort, the firmware developers employed by Purism (and hopefully some community members) can improve power characteristics. I suspect Purism employees have spent most of their time getting the modem firmware and RF-fronted SW into a functional state. There was a blog post somewhere where a Purism employee brought up a call over the air (OTA). I can't find it but that was by far the most important milestone of their effort. Getting past RACH and acquiring a base-station OTA is huge in the industry. The first phase of binary blob development is predominately focused on integrating features while avoiding attach failures and BLER issues. In this first phase, power saving features are typically disabled to make everything else easier to debug. It is safe to say that the Purism employees have neither had the time nor the resources to even start on modem/RF power saving features. *Again, in my opinion, the power problem can be solved but this will be a huge massive incredible exhausting undertaking.*

**Reception:**

As I have explained above, IOT-class modems are not designed for, and do not care for certain features. Certain features are really necessary for a regular smartphone (henceforth refereed to as a "UE") to function well. Some examples are:

1. Mobility. The ability of a UE to switch to new base-stations as the user travels (walking, driving, whatever). This is distinct from the ability of the UE to attach (pass RACH msg 4) to a cell tower from boot or a total signal loss.
2. Compatibility with all LTE bands. This is why Purism has to support four modems and why you the user will likely to have a somewhat unpleasant time setting things up.
3. Interoperability testing vs Standards Regression Testing. Suppose that LTE specs can have 1000 different configurations for a cell network and towers within that network. Large modem vendors rigorously test 100's of possible configurations, even if the carriers (Verizon, Sprint, China Mobil, ...) and the base-station vendors (Huwawei, Nokia, Ericsson, ...) only use a few dozen possible configurations. This means that niche bugs are unfortunately likely to show up.
4. Low-SNR performance. Companies who deploy these modems either place their devices in physical locations that get good SNR (20 dBm ish) or they just attach a giant antenna to get an extra 6-10 dB gain. Users of cellular devices want to still have basic connectivity for voice calls, SMS texts, and notification batches... even if the SNR is bad ([1-bar ~= 7 dB SNR; NOTE: EE's use SNR and SINR interchangeably based on background](https://usatcorp.com/wp-content/uploads/2016/06/lte-singal.png)) users still expect basic functionality. IOT modems do not have the hardware blocks to handle low-SNR signals. This is to keep the chip small and cheap. Some DSP tricks like higher order filter banks, over-sampling, and many other linear algebra tricks likely can not run on the modem in real time, rendering them useless. (wireless channel coherence is often quite short)

What concerns me the most is that in the "Supplying the Demand" post, Mr. Weaver only implies that there is a reception issue by very briefly mentioning an "antenna routing" problem. I do not find the claim plausible. UE base-band antennas are typically PIFA, patch, or Log periodic in design. Depending on many factors which are beyond my knowledge, you can get around 6-15 dB of gain from antennas alone. Even though I am a DSP engineer, my job requires me to have a surface level knowledge of antenna radiation patterns. Up front, I can tell you that antenna placement can not and is not a issue. In the Librem 5 batches that do

not have metal construction. There should be zero problems. Plastic does not interfere with radio waves enough to cause more than 1-1.5 dB loss in the absolute worst case. In the devices with metal bodies, there should be no issue anyway because of [antenna bands.](https://zdnet3.cbsistatic.com/hub/i/r/2019/08/05/01ca94f7-18a5-4fc2-aa7b-fc31fc3a076e/resize/1200x900/108e3cfb8870f30b703ad9ab0ce0901f/galaxy-note-10-3.jpg) The image I linked is a modern ultra-high end device where you can easily see two thin rectangular plastic antenna bands. There is a reason modern antenna bands are so small: it has become incredibly easy (and thus cheep) to mass produce highly directive antennas. This is especially true for for designs intended for UE's. As a student working in a lab on campus, we had a tight budget and needed to buy antennas for a system we were building. For legal reasons, we were operating on the 1.3 GHz band. Unfortunately, this was impossible because all the "off the shelf" (and very cheap) antennas were designed for various cell phone bands. We ended up ordering a custom design (Gerber files from a fellow student) and fabricated 150 large PIFA antennas for ~$100.

In summary, this large paragraph is a justification for the following strong opinion. *I believe there may be serious reception issues with the Liberm 5. These reception issues are not related to antennas. Mr. Weavers in-passing and extremely brief mention of "antenna routing" issues may be the tip for the (reception/SNR) iceberg.*

~~=========================================================~~

I want to make clear that I do not hold ill will against Purism or FOSS mobile efforts. I absolutely hate that any activity on my smartphone goes directly to Google. For years, I have been holing onto a 100-200 dollar class smartphone because use of said device must be kept to a minimum to protect my privacy (I try to keep all my online activity on a laptop that I control). However, this entire post is an opinionated criticism of Purism's hardware choices. At the end of the day, a cellular device that truly protects your privacy (with potential serious hardware and reception issues) is no different than a Android or iOS phone which has had its antennas and RF cards ripped out. A smartphone is only useful when it can be used. Otherwise, a laptop on a WiFi connection with VoIP (and a VPN) will be objectively more useful.

https://redd.it/dnmwlc
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New Video Series Out "How To Use Linux Mint | A Complete Guide"

I just recently finished producing a complete video series on how to use Linux Mint, from the Cinnamon Desktop, to files & folders, installing apps, customizing, and more! I made them to be a resource to all, so please enjoy and feel free to share with new users who might find it a helpful resource:

[https://www.youtube.com/watch?v=kUC9RbrS0q0&list=PLrW4kXWyzgoKKLkdHTH8E5v\_JboLeAITi](https://www.youtube.com/watch?v=kUC9RbrS0q0&list=PLrW4kXWyzgoKKLkdHTH8E5v_JboLeAITi)

​

https://i.redd.it/9dwl04t461v31.jpg

https://redd.it/dnpx3i
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