Graham White: My Notes

Linus Torvalds has previously had some very choice words to say about NVidia with regards their interaction with open source and Linux.  I've spent much of my career using (and battling with) the NVidia drivers on my Linux laptop and these are my notes that make life a little easier and better.  For me, NVidia drivers at home on a PC work pretty well.  They work less well on a laptop where things are a bit more complicated with external screens, hot plugging of screens, suspend, etc.  I've tried the open source alternatives and they really just don't work as well in terms of stability (not that I find the NVidia proprietary Linux drivers especially stable, especially on a modern desktop under Wayland) but also in terms of power management and graphical performance.  Hence, I've always concluded I'm better off running the proprietary drivers.  If it weren't for the fact that the Lenovo Laptops I use at work have their external monitor connections hard wired to the NVidia card then I would probably just turn off the GPU entirely and rely on the embedded Intel GPU.

Installation

Thankfully, this is pretty simple on Fedora due to the packaging at RPM Fusion.   Hence, I think the best way to install the NVidia driver on Fedora is to use the RPM Fusion repository, as follows:

1. Follow the guide at https://rpmfusion.org/Configuration to install both the free and non-free RPM Fusion repositories
2. Install the NVidia drivers (see https://rpmfusion.org/Howto/NVIDIA)

It is also best to set your GPU to "discrete only" mode in your UEFI/BIOS.

Note: there is a highly viable alternative repository that also I've run very successfully at Negativo17 and you can, of course, grab the drivers directly from NVidia via their unix downloads page.

Re-Build the NVidia Kernel Module

There are instances where manually kicking off the re-building of the NVidia kernel module can be useful. This can be done very easily as follows:

$ akmodsbuild --kernels $(uname -r) /usr/src/akmods/nvidia-kmod.latest 
$ sudo dnf reinstall <name-of-the-output-rpm-from-above>

Note that the above will rebuild the NVidia kernel module for the current running kernel. You can swap out the $(uname -r) piece of the command for the version string of any of your installed kernel modules to build for a different kernel that you have.

Create a file /etc/modprobe.d/nvidia.conf with the following content:

options nvidia NVreg_PreserveVideoMemoryAllocations=1
options nvidia NVreg_TemporaryFilePath=/var/tmp
options nvidia_drm modeset=1

These should already be on your system after installation but just in case, make sure you have the following RPMs installed by running:

$ sudo dnf install xorg-x11-drv-nvidia-power nvidia-modprobe

Ensure the nvidia suspend/resume services are enabled:

$ sudo systemctl enable nvidia-suspend.service nvidia-hibernate.service nvidia-resume.service

Note: do not enable the nvidia-persistenced.service as this can cause issues on a single GPU machine such as a laptop

Often, the installation of the NVidia driver can cause the LUKS password prompt to drop back to text mode. This isn't a problem from a functional point of view but it's not so nice to look at as the graphical prompt. If you want to restore the graphical prompt you need to ensure that the NVidia driver is built into your ram disk image. This can be achieved fairly simply, as follows:

Create a file /etc/dracut.conf.d/nvidia.conf and add these lines (note the spaces are required in the quoted strings so that's not a mistake):

add_drivers+=" nvidia nvidia_modeset nvidia_uvm nvidia_drm "
install_items+=" /etc/modprobe.d/nvidia.conf "

With that file in place, you can re-generate your ram disk image by running:

$ sudo dracut -f

Not strictly an NVidia related thing but while I'm on the topic of displays, on HiDPI/4k laptop screens, the console font (seen during the boot process if things go wrong) can be nearly impossible to read as it's far too small. You can resolve this issue by switching your console font to a larger font size.

First, make sure you have the relevant console font(s) installed:

$ sudo dnf install kbd-misc

Next, edit the file /etc/vconsole.conf and change the "FONT=" line to a larger font e.g.

FONT="latarcyrheb-sun32"

With the current release of Fedora Linux being updated to version 40 this week, I find myself upgrading to it on the first day of release (rare for me, I usually wait a couple of months) and getting up-to-speed with the changes in Gnome 46.  My previous post about Gnome focused on my migration to Gnome 3 and the extensions I was using at the time.  During the course of the previous (nearly) 5 years, these have changed quite significantly as the Gnome desktop has grown and as my usage of it has moved on.  Hence, rather than update my old post as I have done in previous years, I thought it time to write a whole new post focusing on how I set up my Gnome desktop today.

So without further ado, this is the list of extensions I'm using right now as I write this post (in alphabetical order):

AppIndicator and KStatusNotifierItem Support

This is one of the few extensions that has stood the test of time with my particular usage of Gnome.  While the free desktop standard continues to specify the classic "icon tray" that was supported by extensions such as TopIcons, in reality few of the modern desktops (I'm referring to Gnome and KDE) support them.  The modern take on the tray icon is an AppIndicator icon and many modern applications are written to use this standard (and perhaps fall back to a tray icon). 

Dash to Panel

This is a more recent discovery for me.  I've previously evaluated Dash to Dock several times and never liked the user experience.  However, the similarly named and with somewhat similar functionality, Dash to Dock has replaced my use of the Window List extension.  It provides a more modern alternative to showing which windows I have open with window previews and suchlike.  It can do considerably more than the way I've configured it, but I have it set just how I like to work with my Gnome top bar still in tact and a minimal bottom bar used for navigating between my open applications.  If you want to try it out with my configuration, I've exported my settings into this GitHub Gist that you can import.

Frippery Panel Favourites

It takes your favourited applications and adds them as a set of icons to the Gnome top panel, making for extra quick access to your commonly used apps.  I tend to flip between using this and just searching for apps via the Super button (windows key).

GTile
This great little extension allows you to easily resize your windows in order to tile them across your display.  I love the side-snapping in Gnome 3 that allows you to size a window to half the screen size.  However, GTile adds an icon to your Gnome Panel that, when clicked, allows you to size to any area of your screen across a pre-defined grid - you can even change the grid size.  Brilliant for usability with lots of on-screen windows at the same time.  It strikes a great balance for me as someone that generally prefers to tile windows but doesn't like a tiling window manager.

Hide Activities Button

This is almost a little bit superfluous for my usage but I found myself never using the activities button (top left) in the Gnome Panel.  The Dash to Panel configuration I have created maintains an activities button (bottom right) which is the place I've grown familiar with in order to use my GUI to switch between desktops (although I generally switch between desktops using keyboard shortcuts).

Pano Clipboard Manager

This is a really great modern take on the clipboard.  Press shift+windows+v and you get a pop up at the bottom of the screen with a graphical representation of your clipboard history.  The extension is clever enough to be aware of various types of clipboard content such as text, images or hyperlinks.  You also get a button on the top panel that allows access to the clipboard, incogneto mode (stops copying stuff to the extension) and settings.

System Monitor Next

Adds little graphs to the Gnome Panel that show resource usage.  The extension is pretty configurable but I have it showing CPU, memory and network utilisation.  This allows me to keep an easy eye on my machine and how loaded it is at the current time.  Extremely useful for spotting those occasional rogue apps that start eating an entire core of my CPU.

A few years back, I decided it would be a good idea to register my little lad on the waiting list for Beaver Scouts and didn't realise at that point in time quite what a journey would be unfolding in front of us.

Needless to say, I ended up volunteering.  I started on a fairly typical journey by offering to help out occasionally and getting DBS cleared.  I found I was attending pretty much every week so from there it was a relatively small step to go into uniform and make my role official.  Four years since I started helping out, I'm an "Assistant Beaver Section Leader" known to the children as "Merlin".

While on the topic of scout names, everyone in my section adopts the name of a creature found in British wildlife.  It's customary for the children to use an adult's scouting name when referring to us.  In fact, they have no idea what our real names are.  I'm not sure why, that's just the way things have evolved.  I wanted to use the name "Goshawk" but at the time our section already had someone named "Hawk" which seemed a bit too similar so I considered other small birds of prey such as "Sparrowhawk" (still too similar), "Hobby" (didn't seem right) and eventually settled on "Merlin".  Now everyone seems to think I'm a wizard and I have to explain the name all the time.  Stupid choice!

Scouting is a great organisation and charity, run at the top level by paid professionals but the majority of the things that happen are as a result of volunteers, such as myself!  The volunteers often go to a lot of lengths, putting in hours of preparation and hard work to make sure all the kids in their section have fun, experience things they wouldn't otherwise do but remain safe.  Hence, I thought I would recount some of the stuff I've been doing since signing up.  Most of this is a total surprise to me as I was never involved in Scouting as a kid so I'm learning and going through the whole thing at the same time as my son.

Safety, DBS and Training

Our primary goal for each meeting and overall plan each term is to have fun while remaining safe.  The safety aspect isn't too onerous, mainly consisting of an initial DBS check that is trivial enough and then risk assessing activities that basically involves common sense to think things through in advance.  There is a reasonable amount of red tape involved in all this that the parents never really see.  There's also training to be done. To be in uniform, one must have a first aid qualification and undertake a bunch of formal training modules, providing evidence to an assessor that you've qualified to pass each module.  This must all be done within 3 years.  Once complete, you're awarded your wood beads - I'm currently most of the way there and have 1 year left to complete the remaining few modules.

Activities

Having never been involved in Scouts previously, pretty much everything that goes on comes as something new (if not a surprise) to me.  Camp fire, songs, cooking, crafting, knot tying and a raft of other outdoor and adventurous activities are all very cool things to get involved with and organise.

Visits and Visitors

I've not been scouting for particularly long, especially when compared to some of our volunteers that have been in the organisation 30+ years.  However, I've already racked up quite a few different venues and experiences:

• Our Scout Hut (obviously), we call it "The Den"
• Other Scout Huts
• 8th Alton
• Bentley
• Four Marks
• RAF Odiham
• Boots Opticians
• Local Library
• Marks and Spencer
• War Memorial
• Chawton House
• Uppark House (national trust)
  
• Scout Camp sites
  
• Garners Field
• Lyons Copse
• Bentley Cops
• Various locations for walks and hikes e.g. Butser Hill
• Local Care Homes
• Our Visitors are varied, e.g.
• Disabled people/groups
• Dance and music groups
• People with specialist skills/knowledge
  

This post continues a long running tradition and series of posts when I'm issued a new laptop at work.  I generally get quite a powerful and interesting machine as I'm a member of the IBM Hursley development laboratory and thus am issued a fairly beefy specification for a majority of desktop use rather than being a more mobile laptop.  I'm issued a new machine approximately every four years so my previous posts are about my:

• Thinkpad P50 (April 2017)
  
• Thinkpad W530 (March 2013)
• Thinkpad T61p (June 2008)

It's interesting to see how the specification of machine has changed over time.  With the slowing (or disappearance) of Moore's Law, the speed advantage of more recent machines has come from other innovations (such as an SSD and an increased number of cores) rather than raw clock speed.  The highlight specifications for the P15 Gen 1 I have are...

• Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (5199.98 bogomips in Linux)
• 32GB DDR4 2933MHz
• Toshiba 512GB SSD XG6 M.2 2280
• 15.6" 3840 x 2160 IPS (non touch)
• Integrated Li-Po 94Wh battery
• Wi-Fi 6
• NVidia Quadro T1000M 4GB
• Front Facing Web Cam, HDMI Out, Headphone, 2x USB3.2, 2x USB-C3.2 Gen 2, GBit Ethernet, Fingerprint Reader, SD card reader

There we have it, the top level specs aren't all that different to the 4 year old P50 machine I had previously.  In fact the CPU speeds have dropped slightly although the P15 does have 12 cores to the P50's 8. RAM and GPU memory have both stayed the same and I still have a 512GB SSD.  Interestingly, the battery is now integrated which has moved away from the long standing removable battery on these top line Thinkpad machines.  There's a huge increase in the screen resolution and I dare say the screen would also have been improved in areas such as peak brightness (600 nits for the P15) and support for Dolby Vision HDR (there's also support for Dolby Atmos sound which will be a bit lost on me for a business machine).  While sounding good, if you put a 4k resolution onto a 15" laptop screen you pretty much need a magnifying glass to see anything so it's more or less useless unless you're consuming 4k video content.  No wonder then that the Gnome desktop defaulted to running in 4k mode but at 200% scale (which I think takes it back down to HD size unless I'm mistaken).

The day-to-day running of the new machine has been pretty good.  Not noticeably different to that of the old machine. This goes to show the lack of improvement in specifications of these new machines in general.  It's something I've noticed with my ageing home machine as well (which is nearly 10 years old) where the processor benchmarks are very similar to today's processors on a core-for-core comparison and I still have things like a decent PCI 3 bus.  It's always nice to have a bit of a refresh though and the thing I'm liking most about the new machine is the addition of the built-in fingerprint reader.  This particular piece of hardware is now fully supported on Linux and very easy to configure using the Gnome settings tool.  It makes logging in with a massive password much less painful.  I hope more apps (such as 1password) will eventually find ways of integrating biometric security on Linux as well.  It's worth noting that this functionality hasn't come at all by accident and has been a lot of hard work and a long road between both Red Hat and Lenovo to ensure that all new Lenovo laptop machines are fully certified to have a hardware configuration that contains drivers and firmware compatible with Linux.

There are, of course, teething troubles with the new machine.  These are mostly related to graphical issues and NVidia.  More recently, I'd taken for granted my old machine just working in these respects.  My old machine had similar teething issues when it was new of course and these were gradually ironed out with driver updates as time progressed.  So right now it's weird to be back in the dark days of having to use the NVidia settings panel to configure the screen resolutions I want as for some reason the binary driver is only showing up the full 4k resolution to xrandr under Linux (yes I'm still using Xorg, not Wayland, yet).  It's also a bit fragile in terms of going into sleep mode and resuming from sleep, it all works but there can be graphical glitches (sometimes and sometimes not) which I may need to restart the gnome shell to cure (Alt+F2 then type r and hit Enter).  While this is frustrating for now, I'm fully expecting driver updates to catch up and this machine will gradually settle down into the same level of graphical performance I was used to on my old machine i.e. no problems at all and no need to open up NVidia settings.  Perhaps the thing that surprises me most about all this though is the very fact that all of this has regressed.  I'm no expert in the graphical stack on Linux but it's rather unfortunate that I seem to experience the same pains and teething problems upon the issue of every new laptop.  It'll all get there.  One day!

In my previous post where I was showing off my IoT Christmas Trees, I described the project and what the trees are intended to do.  This post features the inside track information about how I put the project together.  So the first post is supposed to be non-technical if you will and this post details the info more of interest to those interested in the technical make-up of the project.  Since this is effectively a recipe for how to create one of my IoT Christmas Trees, we'll start with the list of things needed.

Ingredients

For the Tree

• Wood
• Paint
  
• Arduino ESP32
• Micro USB Cable
• Veroboard
• LED String
• Buttons
  

Server and Connection Requirements

Other Useful Bits

• Glue Gun
• Soldering Iron and Solder
• Heat Shrink Tubing
• Wire (22AWG Solid Core)

Putting it all together

The wooden bits

My latest maker project has been running for a good chunk of the year and has been a really cool thing to do to keep me occupied during lockdown since I'm not really one to binge watch box sets.  I've been making Internet connected Christmas trees as gifts for close family.  They're designed to be ambient ornamental decorative pieces with a funky twist of interactivity.  The video I produced probably explains them best...

As you can see from the video, each tree is deliberately different.  I thought it would be more interesting to have a completely different wooden design for each.  My dad did the woodwork which saved me quite a lot of time and allowed me to concentrate on writing the software and doing the electronics not to mention building and painting each tree.  There's a good few hours work in each of these things.

Operation of the trees is pretty simple with the most complicated bit, like with most of these things, being the initial set up to get them onto your WiFi network.  For that, and to explain the basics of how they work along with a bit of troubleshooting information, I wrote a little user manual to go with them.  After all, it will be our closest family members that receive one of these and so I can always help out remotely (and potentially fix any issues that arise).  The left button on each tree cycles round a set of pre-defined colour schemes.  However, these can be changed on a per tree basis should someone want a different colour or configuration.  Similarly, the trees can be operated remotely but I've yet to write a decent interface to do so.  The right button on each tree is where the fun is, causing all the other trees to change light pattern for some period of time.  Again, this is all configurable per tree but by default they all cause the same green and red frenzied light pattern which should be very noticeable in the corner of your room should it occur.

Finally, big thanks to James Sutton and his original iotree project was in no small amount an inspiration for my work here.  Although, the implementations are different both physically and in software there's still a huge amount of overlap.  James was also responsible for running an IoT hackathon at work (we're colleagues) introducing a lot of the technology I would need in order to perform this build.  Thanks again, James!

I've also written more details on the technical implementation.  But, I'll sign this post off with a closer look at each tree in pictures...

This year has seen me doing more in the way of little tech projects at home than I have done for a while, perhaps due to covid lock downs so if that's the case then I'll take this small positive from an otherwise rubbish situation.  Typically for me, these projects have focused around open source projects and some IoT.  More on those in some separate blog posts when I get around to writing them up.  But for now, I wanted to make some notes on my new home server set up.

I've had an array of different low powered home servers of the years that I've previously written about, namely the NSLU2, TinyTuxBox, Joggler and for the past many years a simple ReadyNAS box that I specifically bought for the Intel processor as it made compiling different bits and pieces a whole lot easier back in the day.  However, I have recently relegated the ReadyNAS box from home serving duties, keeping it only for its native NAS services because using it for other things has become increasingly difficult without updating the entire base OS (which is possible by I'm reluctant to do) due to down level software libraries like an ancient version of openssl.

In with the new then and I moved away from Intel architecture as it's now so much easier to compile for Arm chips and went with the, wait for it, drum roll, rather obvious choice of a Raspberry Pi 4.  Specifically, a Pi 4 Model B, 4GB.  I've paired it with the official Pi case power supply, micro HDMI cable and shoved in an A2  SanDisk Extreme 64GB SDXC card.

And so to the notes, my initial target for this new box would be as follows:

• The Lounge self hosted web based IRC interface
  
• A Mosquitto MQTT broker
• Node Red for home automation event processing
• An NGINX reverse proxy
  
• letsencrypt certificates for all of the above
  

The Lounge

It's not every day I find myself publishing a new project to open source and even less so when that requires release approval at work.  I hope, over the years, I've written some useful bits and pieces and this time around I was keen to publish my work on the Internet rather than internally within the company.  This requires following due process of course and seeking the relevant approval for the publication to take place.

Fortunately, in the right circumstances, IBM are very amenable to releasing code to open source.  I was convinced enough that a NetworkManager plugin to add to the existing list of VPN plugins would not conflict with the business that an open source approval would be fairly trivial.  Happily, I was correct, and going through the process wasn't too arduous with a few forms to fill in.  These were, of course, designed much more for bigger releases than I planned so vastly over-engineered for this particular release but at least due diligence was applied.

On to the project and the code.  It's not a world-changer but a small VPN plugin for NetworkManager to drive Cisco AnyConnect and made available as NetworkManager-anyconnect on GitHub.  So I now know more than I'd care to mention about the inner workings of NetworkManager VPN plugins.  They're not very well documented (hardly documented at all in fact) so they're quite hard work to produce by looking over existing code in available plugins.  I started off from the OpenVPN plugin which turned out to be a mistake as the code base is vastly bigger than that required for a plugin as simple as the one I wanted to write.  Were I to start again, I would recommend starting from the SSH VPN plugin instead as this is actually very nicely set out and doesn't include a lot of the shared bloat that comes with other plugins that are formally a part of NetworkManager.

• 12 minutes and 14 seconds on my CPU
• 1 minutes and 14 seconds on my GPU

• Custom Built Home PC
• Intel Core i5-3570K CPU @ 3.40GHz (4 cores)
• 16GB RAM
• NVidia GeForce GTX 1660 (CUDA Compute Capability 7.5)
• Fedora 30 Workstation running kernel 5.2.9-200.fc30.x86_64

• dnf install xorg-x11-drv-nvidia akmod-nvidia xorg-x11-drv-nvidia-cuda