Linux on Chase the Devil

Jack Audio in Opensuse Tumbleweed

Mon, 22 Dec 2025 17:27:00 +0000

I struggled a bit having Jack Audio Connection Kit working in Opensuse Tumbleweed. My error was to install the jack package. The solution is actually extremely simple: use pipewire-jack instead of jack.

sudo zypper in pipewire-jack qjackctl

OpenSuse Tumbleweed to the Rescue

Thu, 06 Feb 2025 12:56:42 +0100

I recently upgraded a desktop computer, and to my surprise, the new motherboard was not fully supported by most Linux distributions. The main culprit was the network adapter, although the secure boot setup gave me lots of troubles as well. I had only a small usb key (2GB) and most (all?) live distributions do not fit on 2GB anymore. With the exception of Ubuntu images, I did not manage to boot from USB hard drive where I dumped the live image ISO, due to Secure boot related issues, even when disabling the feature or changing the settings in the BIOS. Using the small USB key worked with Secure boot enabled only.

Desktop Linux in 2022

Wed, 26 Oct 2022 07:56:42 +0100

I have been a long time user of Fedora at work and have been happy quite happy about it. Around 6 months ago, I moved to Manjaro under VirtualBox in a Windows host, because the company imposes the use of a VPN client that does not run on Linux. It’s much less great for several reasons:

VirtualBox makes everything graphics much slower. It is still way better than WSL2 as I found WSL2 to be a poor man’s Linux, where graphics is via some half broken X11 client for Windows. With VirtualBox, programming is ok, watching videos is not (you need to use the host for that). Something relatively neat is that the VM can be run on any other host, including a Linux host by just copying the vm file.
I picked Manjaro out of curiosity and because it was perhaps faster/more optimized than Fedora. I don’t have too many issues with it. But I found out that the use of AUR packages would frequently break on upgrades. Futhermore, it is updated less frequently than Fedora, which is a bit surprising for a rolling release. I also installed it with ext4. With hindsight, I think both choices were poor, Fedora with brtfs is the way to go, or some Ubuntu variant.
Work also imposes various antivirus programs which tend to always keep the cpu busy.

Overall I am still much more productive than with a raw Windows, which is surprisingly slow for many software development related tasks. Having to deal more with Windows showed me how slow the system is, and how poor the experience is. Before using it again (after many years completely off it), I had started thinking it was good (well, it does crash much less than back in the days).

Github and SSH setup

Mon, 16 Aug 2021 07:56:42 +0100

Github recently moved to support only ssh access via public/private keys. As I use github to host this blog, I was impacted.

The setup on Linux is not very complicated, and relatively well documented on Github itself but all the steps are not listed in a simplistic manner, and some Google search is still required to find out how to setup multiple private keys for various different servers or different repos.

Samsung Wireless Printer under Fedora 25

Thu, 26 Jan 2017 09:55:32 +0100

This is a note for those who want to setup a Samsung wireless printer under Linux. It is quite simple, this forum post helped me, the actual useful steps on Fedora 25 are:

download tar.gz linux driver from Samsung website. As root, unpack & install:

tar xvzf SamsungPrinterInstaller.tar.gz 
cd uld
./install.sh

in the printer menu, lookup for the wireless key (8 digits),
connect to the printer Wifi network with a computer using the wireless key,
enter the network gateway IP, this is typically http://192.168.3.1,
click on Login with user “admin” and password “sec00000”,
open the network wifi settings and select “Easy Wi-Fi Settings”,
connect back to your wireless network,
add the network printer via the printer settings wizard, or alternatively through CUPS interface http://localhost:631.

That’s it. Printer and scanner will then work on your local Wi-Fi network.

Power management and XFCE under Fedora 25

Thu, 19 Jan 2017 09:55:32 +0100

The gnome shell has been crashing on me more regularly lately. XFCE is a good and fast more tradional desktop, but, from past experiences, it does not play well with power management if you only install it via

dnf install @xfce-desktop-environment

My typical experience is a black screen after resuming from suspend (sometimes, not always), or hibernate (always) and most of the time I end up just rebooting. It turns out this is all caused by the interaction between the gdm login daemon and xfce. Moving to the lightdm login daemon instead fixes those issues for Fedora 25:

Linux Desktops in 2015

Wed, 24 Jun 2015 18:53:00 +0000

I seem to never be entirely happy with any of the linux desktops these days. I have used XFCE on Ubuntu quite a bit in the past year, it mostly works, but I still had minor annoyances:

sometimes (rarely) my laptop would not wake up from sleep.
notifications sometimes keep popping up too much.
on my desktop, experienced strong tearing issues with the Radeon graphic card, except with some very specific combination of video player settings and desktop settings (and then I had annoying redraw issue when pushing volume up/down in movies).

I am satisfied with two different approaches since:

GTK 3.0 / Gnome 3.0 annoyance

Sun, 08 Feb 2015 22:30:00 +0000

It’s quite incredible that Gnome 3.0 was almost an identical mess as KDE 4.0 had been a year or two earlier. Both are much better now, more stable, but both also still have their issues, and don’t feel like a real improvement over Gnome 2.0 or KDE 3.5.

Now the main file manager for Gnome 3.0, Nautilus has buttons with nearly identical icons that mean vastly different things, one is a menu, the other is a list view. Also it does not integrate with other desktops well from a look and feel perpective, here is a screenshot under XFCE (KDE would not look better).The push for window buttons inside the toolbar makes for a funny looking window. In Gnome Shell, it’s not much better, plus there are some windows with a dark theme and some with a standard theme all mixed together.

An SSD instead of a laptop

Tue, 04 Feb 2014 15:45:00 +0000

Last week, my work laptop died after spilling out some water on its keyboard inadvertently. Fortunately, its SSD was intact.

As the laptop SSD connector (SATA) and power follow the desktop computers standards, and as I use Linux, I just plugged the SSD to my home desktop and booted off the SSD. I had to change slightly the X configuration but otherwise everything worked. Linux is great for that

The same way, I just plugged the SSD to the desktop at work and it worked. Instead of carrying a laptop, I carry now my small and ultra-light SSD.

Random Hardware Issues

Mon, 06 Jan 2014 18:44:00 +0000

Today, after wondering why my desktop computer became so unstable (frequent crashes under Fedora), I found out that the micro usb port of my cell phone has some kind of short circuit. My phone behaves strangely in 2014, it lasted nearly 1 week on battery (I lost it for half of the week), and seems to shutdown for no particular reason once in a while.

On the positive side, I also discovered, after owning my monitor for around 5 years, that it has SD card slots on the side, as well as USB ports. I always used the USB ports of my desktop and never really looked at the side of my monitor…

Arbitrage Free SABR - Another View on Hagan Approach

Sat, 14 Dec 2013 00:56:00 +0000

Several months ago, I took a look at two interesting recent ways to price under SABR with no arbitrage:

One way is due to Andreasen and Huge, where they find an equivalent local volatility expansion, and then use a one-step finite difference technique to price.
The other way is due to Hagan himself, where he numerically solves an approximate PDE in the probability density, and then price with options by integrating on this density.

It turns out that the two ways are much closer than I first thought. Hagan PDE in the probability density is actually just the Fokker-Planck (forward) equation.

The \(\alpha D(F)\) is just the equivalent local volatility. Andreasen and Huge use nearly the same local volatility formula but without the exponential part (that is often negligible except for long maturities), directly in Dupire forward PDE:

A common derivation (for example in Gatheral book of the Dupire forward PDE is to actually use the Fokker-Planck equation in the probability density integral formula. Out of curiosity, I tried to price direcly with Dupire forward PDE and the Hagan local volatility formula, using just linear boundary conditions. Here are the results on Hagan own example:

The Local Vol direct approach overlaps the Density approach nearly exactly, except at the high strike boundary, when it comes to probability density measure or to implied volatility smile. On Andreasen and Huge data, it gives the following:

Better Fonts in Fedora than in Ubuntu

Sat, 31 Aug 2013 13:36:00 +0000

By default, text in Fedora 19 looks ok but not great. There are good tips to improve fonts on http://fedorasolved.org/Members/khaytsus/improve-fonts

As root user here is what need to be done:

cd /etc/fonts/conf.d

ln -s /usr/share/fontconfig/conf.avail/10-autohint.conf

ln -s /usr/share/fontconfig/conf.avail/11-lcdfilter-default.conf

yum install freetype-freeworld

Reboot, then, in gnome-tweak-tool choose hinting = slight, and antialiasing = rgba. I also choose the liberation sans and liberation mono fonts.

I am not sure which one did the trick, but it looks much better (even better than my laptop under Ubuntu, not sure why).

Giving Fedora Another Chance

Wed, 14 Aug 2013 22:15:00 +0000

I have had some stability issues with the Ubuntu 13.04 on my home computer, not on my laptop. It might be related to hard disk encryption (out of curiosity I encrypted my main hard drive in the installer option, resulting in a usable but quite slow system - it’s incredible how much the hard drive is still important for performance). I did not have any particular issue on my work laptop with it.

Unity vs KDE in Virtualbox

Wed, 10 Jul 2013 23:17:00 +0000

The other day I installed the latest Ubuntu 13.04 under a VirtualBox virtual machine using Windows as host. To my surprise, unity failed to launch properly on the virtual machine reboot, with compiz complaining, something I have sometimes seen on my work laptop. It’s more surprising in a VM since it is in a way much more standard (no strange graphic card, no strange driver, the same stuff for every VirtualBox user (maybe I’m wrong there?)). I therefore installed KDE as a way to bypass this issue. Not only it worked, but the UI was much faster: there was some very noticeable lag in Unity, slow fade in fade out effects, when it worked before the reboot.

OpenSuse 12.2

Wed, 14 Nov 2012 10:12:00 +0000

After too many upgrades of Ubuntu, and switching from Gnome to KDE and back, my Ubuntu system became behaving strangely in KDE: authorization issues, frequent crashes, pulseaudio and ardour problems. I decided to give another try to OpenSuse, as Linux makes it easy to switch system without losing too much time reinstalling the useful applications.

It’s been only a few days, but I am pleasantly surprised with OpenSuse. It feels more polished than Kubuntu. I could not point out to a specific feature, but so far I have not had to fiddle with any configuration file, everything works well out of the box. Somehow Kubuntu always felt flaky, read to break at any moment, while OpenSuse feels solid. But they should consider changing the default font settings in KDE to take advantage properly of antialiasing and pretty fonts (it’s only a few clicks away, but still the default is not the prettiest).

Pretty Fonts in Chrome with Linux

Wed, 12 Sep 2012 18:06:00 +0000

It's a bit incredible, but in 2012, some linux distros (like Fedora, or Kubuntu) still have trouble to have pretty fonts everywhere. I found a nice tip initially for Google Chrome but that seems to improve more than Chrome: create ~/.fonts.conf with the following:

[match target="font"]
[edit name="autohint" mode="assign"]
[bool]true[/bool]
[/edit]
[edit name="hinting" mode="assign"]
[bool]true[/bool]
[/edit]
[edit mode="assign" name="hintstyle"]
[const]hintslight[/const]
[/edit]
[/match]

replace [ and ] with brackets < and >

Update from 2013 - This can be done system wide, see http://chasethedevil.blogspot.com/2013/08/better-fonts-in-fedora-than-in-ubuntu.html

Fedora 17 vs Ubuntu 12.04

Wed, 12 Sep 2012 18:03:00 +0000

I had the bad idea to upgrade to the beta Ubuntu 12.10. Something awfully broke in the upgrade. After too much struggling with apt-get & dpkg, I decided to install Fedora 17.

Strangely Fedora feels much faster than Ubuntu 12.04 (the boot time especially). Yum seems also faster than apt-get, especially the update part. Also while the Unity dock is not bad (better than gnome shell dock), the Unity dash thing just makes me crazy, the gnome shell activities, while close, are much easier to use.

But it needs a bit more steps to install, although I had no problem to install nvidia drivers, Oracle 11g xe, Java, MP3, nice fonts, nice icons thanks to the guides here and there. SSD Trim instructions are the same (basically use "discard" instead of "default" in /etc/fstab). I have the most troubles with Oracle: somehow the start script does not work and I currently log in as "oracle" and start /u01/app/oracle/product/11.2.0/xe/config/scripts/startdb.sh from there (after having added the proper .bashrc for this user)

I even managed the peculiarities of my laptop a similar way as ubuntu: I want Nvidia card when plugged in to a monitor (to be able to use it) and Intel card when not (to be able to use the LCD screen). My solution is to use the boot screen (in reality one just need to restart X11): this amounted to add a "hdmi" in "/etc/grub.d/40_custom" and creating a link to "/etc/rc3.d/S10DriverSelect" the following script (a dirty hack):

#!/bin/sh
if grep -q hdmi /proc/cmdline
then
if [ -d /usr/lib64/xorg/modules.bak/extensions/nvidia ];
then
cp -f /etc/X11/xorg.conf.hdmi /etc/X11/xorg.conf
mv /usr/lib64/xorg/modules.bak/extensions/nvidia /usr/lib64/xorg/modules/extensions/
fi
else
if [ -d /usr/lib64/xorg/modules/extensions/nvidia ];
then
cp -f /etc/X11/xorg.conf.intel /etc/X11/xorg.conf
mv /usr/lib64/xorg/modules/extensions/nvidia /usr/lib64/xorg/modules.bak/extensions/
fi
fi

Linux distros are really becoming closer in terms of configuration, LSB has made great progress.

Edit from November 29: After a few weeks, I noticed that the system was quite unstable unfortunately. As a result, I moved back to Ubuntu on my laptop. I am running OpenSuse on my home computer. 1 year later, I am back to Fedora 19, 20 on my desktop - no stability issue, I prefer Gnome over KDE.

Gnome Shell more stable than Unity on Ubuntu 12.04

Thu, 14 Jun 2012 12:01:00 +0000

Regularly, the unity dock made some applications inaccessible: clicking on the app icon did not show or start the app anymore, a very annoying bug. This is quite incredible given that this version of Ubuntu is supposed to be long term support. So I decided to give one more chance to Gnome Shell. Installing it on Ubuntu 12.04 is simple with this guide.

To my surprise it is very stable so far. Earlier Gnome Shell versions were not as stable. After installing various extensions (dock especially) it is as usable as Unity for my needs. It seems more responsive as well. I am not really into the Unity new features like HUD. It sounds to me like Ubuntu is making a mistake with Unity compared to Gnome Shell.

To make an old extension support latest Gnome Shell version, it is sometimes necessary to update the extension metadata with what's given by gnome-shell --version. For the weather extension you can just edit using gedit:

sudo gedit /usr/share/gnome-shell/extensions/weather@gnome-shell-extensions.gnome.org/metadata.json

KDE 4.8 finally has a dock

Fri, 27 Jan 2012 13:38:00 +0000

KDE 4.8 finally has a dock: you just have to add the plasma icon tasks. Also the flexibility around ALT+TAB is welcome. With Krusader as file manager, Thunderbird and Firefox for email and web, it is becoming a real nice desktop, but it took a while since the very bad KDE 4.0 release.

It is easy to install under ubuntu 11.10 through the backports and seems very stable so far.

Something quite important is to tweak the fonts: use Déjà Vu Sans instead of Ubuntu fonts, use RGB subpixel rendering, use Crisp desktop effects. With those settings, KDE looks very nice. It's sad that they are not default in Kubuntu.

Update March 2013: It's been a while now that it is in the standard Ubuntu repositories and I believe installed by default, one has just to remove the task manager widget add the icon task widget:

One can also change the settings using a right click (I find useful not to highlight the windows) and it can look like:

Gnome 3 not so crap after all

Wed, 30 Nov 2011 18:11:00 +0000

In a previous post, I was complaining how bad Gnome 3 was. Since I have installed a real dock: docky, it is now much more usable. I can easily switch / launch applications without an annoying full screen change.

In addition I found out that it had a good desktop search (tracker). The ALT+F2 also does some sort of completion, too bad it can not use tracker here as well.

So it looks like Gnome 3 + gnome-tweak-tool + docky makes a reasonably good desktop. XFCE does not really fit the bill for me: bad handling of sound, bad default applications, not so good integration with gnome application notifications.

Now if only I found a way to change this ugly big white scrollbar…

Gnome 3, Unity, Crap

Wed, 17 Aug 2011 19:09:00 +0000

After the upgrate to Ubuntu 11.04 I was directly on Unity. Having a dock on the left side is nice, but unfortunately, it has various bugs which makes it sometimes annoying. Also the menu on top like Mac Os X is not a bad idea, but it breaks many apps (for example Picasa). Then there is the scrollbar insanity, it’s almost impossible to click on to scroll, and again breaks in some apps (for example Eclipse). Fortunately one can disable all of that and go back to the old Gnome 2.

Pulseaudio Nightmares - Pure ALSA to the Rescue

Sat, 27 Jun 2009 18:19:00 +0000

In the latest stable Ubuntu (9.04), pulseaudio still does not work reliably on my hardware (intel HDA with digital SPDIF out). I upgraded to 9.10 and had even more problems. Sound always worked on boot, but often broke down after a while. And I could not find easy ways to make it work other than rebooting... Killing/restarting pulseaudio, looking at the processes using snd did not work.

One thing works wonderfully, pure ALSA. To have multilple apps sharing ALSA, I just use dmix. As I use digital out, there is no mixer, but ALSA can provide one through softvol. It works really well. ALSA is already not that simple to configure/setup properly, but with pulseaudio on top, welcome to your worst configuration nightmares.

Here is the .asoundrc I use:

 
pcm.amix {
   type dmix
   ipc_key 50557
   slave {
       pcm "hw:0,1"
       period_time 0
       period_size 1024
       buffer_size 8192
   }
   bindings {
       0 0
       1 1
   }
}

pcm.softvol {
    type            softvol
    slave {
        pcm         "amix"      #redirect the output to dmix (instead of "hw:0,0")
    }
    control {
        name        "PCM"       #override the PCM slider to set the softvol volume level globally
        card        0
    }
}


pcm.!default {
    type            plug
    slave.pcm       "softvol"   #make use of softvol
}

Linux Audio State = Miserable

Thu, 19 Mar 2009 12:39:00 +0000

There are lots of programs for playing MP3 under linux, a few dealing decently with big libraries. But when you start looking for a program that does crossfade well and manage big libraries easily - there is nothing.

Rhythmbox does some crossfade, but crashes when you move manually in the song. Audacious does some crossfade but regularly crashes with crossfade plugin.

The real alternative are AIMP2 or Foobar2000 in Wine. It is quite incredible that you can have good solid crossfade in wine and not natively in Linux.

Why ArchLinux Is Better Than Ubuntu

Fri, 14 Nov 2008 10:41:00 +0000

It has been now a week since I have installed ArchLinux on my home computer. I daily use Ubuntu 8.10 at work.

Since the Ubuntu upgrade from 8.04 to 8.10 I have had problems with my Xorg settings. I just found out the nvidia-settings utility does not manage to save the configuration anymore. So I have to lookup on google and try to fix it. And that annoys me. That annoys me because the promess of Ubuntu is that everything works out of the box. In reality, you have to mess with the configuration as much as with ArchLinux.

KDE 4.1.3 (again) on ArchLinux

Sat, 08 Nov 2008 15:54:00 +0000

I tried another silly thing with Linux, ArchLinux. The setup is quite rough as you have to edit many config files manually. But if you know a bit your way around it takes only a few hours to have everything running well. The installation manual on the wiki is detailed enough to correct all eventual mistakes humans do.

I decided to try once more KDE 4 on it, as at first it was just a silly experiment: I was really not sure ArchLinux would be workable. In the end I am pleasantly surprised, KDE 4.1.3 is way way better than any other versions of KDE I have tried before. It is stable and quite pretty. It took the team a lot of time to get there but now I think KDE 4 is a very good window manager, pleasant to use.

Firefox 3

Wed, 18 Jun 2008 11:26:00 +0000

I tried Firefox 3 twice before, while it was in alpha and beta. I was not impressed at all, it seemed buggy (normal for alpha) and I found the new location bar behavior unintuitive. It did not seem that much faster either. So I always quickly went back to Firefox 2.

I tried again recently, funnily, because of a bad Kernel update. One day, after a kernel update, my laptop started to run only at a max of 800Mhz, I did not notice it immediately. I thought wow Firefox 2.0 is really slow with gmail, maybe I should try Firefox 3 again. I did and worked a few days without noticing the processor speed difference that much. Firefox 3 at 800Mhz is as fast as Firefox 2.0 at 2Ghz. It is only after struggling with very long compilation time related to my work that I thought something was wrong.

As usual with Linux troubles, solution are strange but not too hard to find out. I just had to add a processor.ignore_ppc=1 kernel parameter for the kernel to behave properly again.

Yesterday I installed Firefox 3 on a MacBook, and I was really impressed by its speed. I felt faster than Safari. And now I got used to the new location bar behavior, I would not go back (I think the behavior improved after the betas as well).

Another interesting browser these days, especially for bloggers, is Flock 2 (based on Firefox 3).

Fedora Linux & Apple Bluetooth Keyboard

Thu, 05 Jun 2008 20:05:00 +0000

It took me a long time to have the Apple Bluetooth Keyboard (slim aluminium model) working well with Fedora 9. Thanks to the Ubuntu documentation, it is quite easy to establish a connection manually through hidd commands. It was unfortunately much more difficult to have it automatically recognized and not disconnected after a few minutes without use.

The following configuration should work with any other distro and probably other bluetooth keyboards as well.

2 configurations files need to be updated to make it work:

/etc/default/bluetooth should contain the following, with the mac address replaced by the one from your keyboard (hidd --search to see it).

BLUETOOTH_ENABLED=1

HIDD_ENABLED=1
HIDD_OPTIONS="--timeout 8 --connect 00:1D:4F:A7:15:CC --server"

/etc/bluetooth/hcid.conf should be appended with

device 00:1D:4F:A7:15:CC {
name "Apple Wireless Keyboard";
auth enable;
encrypt enable;
lm master;
}

The 2 tricky parameters are "lm master" (makes it connect automatically), and "--timeout 8" that makes it not disconnect contrary to what the option tells. Without the option the timeout of the keyboard is about 11 minutes. If the computer timeout is lower, the connection will be reestablished automatically, thus the value of 8.

Jun 16th update: I still had disconnections, the only way I found to get rid of them was to patch the kernel. I find surprising it was needed, I thought there would have been enough people complaining that the patch would have already been applied in Fedora kernel.

Fedora 9 Already Stable

Fri, 25 Apr 2008 11:33:00 +0000

Fedora 9

I “upgraded” my home computer to Fedora 9. “upgraded” because I reinstalled the OS instead of using the upgrade procedure. I have had so many issues with “partial” upgrades in the past (with any distro).

Although it is the preview/RC1 version, Fedora 9 is already as stable as a release IMHO. No issues so far, it feels more polished than Fedora 8. OpenJDK 1.6 is there. Firefox 3 is there. Not a single problem with kernel 2.6.25 (while I had plenty with the 2.6.24 ones).

Ubuntu 7.10 vs Fedora Core 8 - Gutsy vs Werewolf

Tue, 20 Nov 2007 16:23:00 +0000

I was pretty happy with Ubuntu 7.10, but when Fedora 8 came out I decided to give it a try. Last time I tried it it was Core 2 or something like that, and it was NOT good.

At first Fedora 8 looks quite good, has a good Live CD install, reminiscent of Ubuntu. The positive side is that it is based on the latest Kernel. It manages my Thinkpad T42 very well (suspend, hibernate work). But after a few days, one notice Fedora is not as stable as Ubuntu, for example: