wolf

Hello Linux community,

I need some help with shutting down my laptop when the battery reaches a low percentage.

I am using Debian 12 with the GNOME desktop. WARNING: Minimal installation with self selected packages.

What I want to achieve is, that the laptop just does a 'halt -p' or shuts itself down when the battery is below 20%.

What I did so far:

• Look into GNOME settings in the power settings area and I found nothing helpful
• I edited /etc/Upower/UPower.conf with my settings and changed the CriticalPowerAction to PowerOff, ensured the upower daemon is running via systemctl status and rebooted. The result was that I get a warning popup message in GNOME when the battery load reaches 21%, but it does not shutdown the laptop at 20% or under 20%, although I get another pop up announcing that the laptop would be shutdown
• I ensured laptop-mode-tools and gnome-power-manager settings are installed

Any help/pointers for further help would be highly appreciated.

I posted about ZRAM before, but because of my totally unscientific experiment, personal experience and the common question, which Linux to run on potatoes...

First, I tweaked ZRAM for my use-case(s) on my hardware, this settings might not be right for your use-cases or your hardware!

My hardware is a netbook with an Intel Celeron N4120 and 4G RAM (3.64G usable).

When I recently played around with ZRAM settings, it felt like the zstd algorithm made my netbook noticeable more sluggish. It never felt sluggish with lzo-rle or lz4.

In a totally unscientific way, I rebooted the computer several times (after a complete update of everything), executed my backup script several times, and measured the last 3 executions. (Didn't touch the netbook during the runs.) The bottleneck of the backup script should not be ZRAM, but it is some reproducible workload that I could execute and measure.

To my surprise, I could measure a performance difference for my backup scripts, lz4 was consistent fastest in real and sys time w/o tweaks to vm.page-cluster!

Changing the vm.page-cluster to 0 further enhanced the speed for lz4, but with this one toggle, all of a sudden zstd is as fast as lz4 in my benchmark and runs with a more consistent runtime.

Changing the vm.swapiness to 180 decreased the speed for lz4, to my surprise.

Obviously the benchmarks are not 100% clean, although the trend for my workload was clearly in favor of lz4/zstd.

To the best of my knowledge, I ended up with nearly the same tweaks that Google makes for ChromeOS:

• zstd as algorithm (I think ChromeOS uses lzo-rle)

• 2*ram as ram-size

• vm.page-cluster = 0

• Install/enable systemd-oomd

vm.page-cluster = 0 seems like a no-brainer when using ZRAM, on my netbook it is literally the switch for 'fast' mode.

In summary: ZRAM makes my netbook totally usable for everyday tasks, and with tweaking the above settings I run Gnome 3, VS Code and Firefox/Evolution w/o trouble. (Of course, Xfce4 on the same machine is still noticeable more performant.)

I wonder if we should recommend to people asking for a lightweight distribution for potatoes to check/tweak their ZRAM settings by default.

Anyway, I would be interested in experiences from other people:

1. Any other tweaks on my ZRAM or sysctl for potatoes which made a measurable difference for you?
2. Any other tips to improve quality of life on potatoe machines? (Besides switching to KDE, LXDE, Xfce, etc. ;-))
3. Any idea why vm.swapiness didn't improve my measurements? To my understanding it should basically have cached more of my files in ZRAM, making the backup run faster. It even slowed the backup down, which I don't understand.

Edit:

• zstd beats lz4 on my machine for my benchmark when vm.page-cluster=0!

... I mean, WTF. Mozilla, you had one job ...

Edit:

Just to add a few remarks from the discussions below:

1. As long as Firefox is sponsored by 'we are not a monopoly' Google, they can provide good things for users. Once advertisement becomes a real revenue stream for Mozilla, the Enshittification will start.
2. For me it is crossing the line when your browser is spying on you and if 'we' accept it, Mozilla will walk down this path.
3. This will only be an additional data point for companies spying on you, it will replace none of the existing methodologies. Learn about fingerprinting for example
4. Mozilla needs to make money/find a business model, agreed. Selling you out to advertisement companies cannot be it.
5. This is a very transparent attempt of Mozilla to be the man in the middle selling ads, despite the story they tell. At that point I can just use Chrome, Edge or Safari, at least Google has expertise and the money to protect my data and sadly Chrome is the most compatible browser (no fault of Mozilla/Firefox of course).
6. Mozilla massively acts against the interests of their little remaining user base, which is another dumb move made by a leadership team earning millions while kicking out developers and makes me wonder what will be next.

Interesting workflow.

Of course the fact that Nate uses Thunderbird instead of KMail explains a lot. One day I hope KMail/Akonadi get the attention/work they need to become viable options.

Interesting workflow.

Of course the fact that Nate uses Thunderbird instead of KMail explains a lot. One day I hope KMail/Akonadi get the attention/work they need to become viable options.

Interesting times ahead! I am really looking forward to the Leap Micro release and hope it advances the state of the art. :-)

Solved: The files are encrypted, see stackoverflow

Hope it is ok to ask technical questions in this channel!

I found a folder of files on one of my back drives which was copied from a very old Sony Ericson cell phone or a SAMSUNG Galaxy S2.

The folder is called DCIM and in a sub folder called Camera there are files with a .jpg extension.

This files are not standard JPG files. They start with the following header:

0000000 0000 0000 3900 c0d8 ac5f d196 2d63 2421
0000010 0003 0200 0000 0010 0200 2d8c 0904 0103
0000020 0000 0000 0000 0000 e960 2861 7025 ba0e
0000030 2424 dcfa 3e3b ee64 0800 c87b a43a a90d
0000040 7287 b815 7ca4 9680 ed65 6216 5f08 4f43
0000050 534e 4c4f 0045 0000 9000 b3e9 1333 92b9
0000060 0002 0000 0000 0000 0000 0000 0000 0000
0000070 0000 0000 0000 0000 0000 0000 0000 0000

And the last bytes look like this:

039fea0 60ff 01fa 6b1e 8ef5 7c6f e69f fd9e 1589
039fef0 2199 dbd9 13fe 337d 2e9f d862 e252 080d

(obtained via hexdump -n 1024 filename.jpg).

The file command just returns 'data'.

The jpgrecovery command simply does not process this files.

The strings command finds an embedded string "_CONSOLE" !

If I open the file in a file viewer (shotwell, GIMP, Firefox, Google Chrome), I get the error that the file starts with 0 0, which is correct, as seen in the above hexdump.

Using identify from the imagemagick package results in:

20140207_142030.jpg JPG 0x0 16-bit sRGB 3.625MiB 0.000u 0:00.002
identify-im6.q16: Not a JPEG file: starts with 0x00 0x00 `20140207_142030.jpg' @ error/jpeg.c/JPEGErrorHandler/338.

All this commands were executed on Debian 12.

I have hundreds of files with this JPG extension and for each file the header is starting with 0 0 in this folder, so I assume the problem is not corruption of one file.

My questions:

1. What kind of file format is this?
2. How can I convert the files to JPGs?

Edit: Added the output of some suggested data/commands to questions Edit: Mark as solved, thanks to @hades@hades@lemm.ee .

Thanks a lot to everyone helping to figure this out/pointing me in the right direction! <3

I am not a member of the Anti-Snap crowd (although of course the server sources should be open source), but there is obviously a lot to improve. Flathub/Flatpak should also take note!

There is a similar question on the site which must not be named.

My question still has a little different spin:

It seems to me that one of the biggest selling points of Nix is basically infrastructure as code. (Of course being immutable etc. is nice by itself.)

I wonder now, how big the delta is for people like me: All my desktops/servers are based on Debian stable with heavy customization, but 100% automated via Ansible. It seems to me, that a lot of the vocal Nix user (fans) switched from a pet desktop and discover IaC via Nix, and that they are in the end raving about IaC (which Nix might or might not be a good vehicle for).

When I gave Silverblue a try, I totally loved it, but then to configure it for my needs, I basically would have needed to configure the host system, some containers and overlays to replicate my Debian setup, so for me it seemed like too much effort to arrive nearly at where I started. (And of course I can use distrobox/podman and have containerized environments on Debian w/o trouble.)

Am I missing something?

What are your 'defaults' for your desktop Linux installations, especially when they deviate from your distros defaults? What are your reasons for this deviations?

To give you an example what I am asking for, here is my list with reasons (funnily enough, using these settings on Debian, which are AFAIK the defaults for Fedora):

• Btrfs: I use Btrfs for transparent compression which is a game changer for my use cases and using it w/o Raid I had never trouble with corrupt data on power failures, compared to ext4.

• ZRAM: I wrote about it somewhere else, but ZRAM transformed even my totally under-powered HP Stream 11" with 4GB Ram into a usable machine. Nowadays I don't have swap partitions anymore and use ZRAM everywhere and it just works (TM).

• ufw: I cannot fathom why firewalls with all ports but ssh closed by default are not the default. Especially on Debian, where unconfigured services are started by default after installation, it does not make sense to me.

My next project is to slim down my Gnome desktop installation, but I guess this is quite common in the Debian community.

Before you ask: Why not Fedora? - I love Fedora, but I need something stable for work, and Fedoras recent kernels brake virtual machines for me.

Edit: Forgot to mention ufw

I am playing around with Fedora Silverblue and openSUSE Aeon and I really like the painless updates.

Still, my daily driver for some years now is Debian, and I have a decent setup via Ansible - everything just works for me.

My question is mostly to long term Linux users, which use Linux in a professional context and jumped from a distribution like Fedora, Ubuntu, openSUSE or Debian to NixOS, Silverblue, Aeon etc.

What is your experience? How did your workflows change on your immutable Linux distribution? Did you try immutable and went back to a more traditional distribution - why? How long are you running the immutable distribution and what issues and perks did you run into?