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Archive for the ‘Hackweek’ Category

fonts @ openSUSE

February 17th, 2015 by

Since I maintain fontconfig, time to time I hear contradicting opinions which font families should be used in the system if not said otherwise, i. e. which families should be preferred for sans, serif and monospace generic aliases and how they should be rendered. Bug reports I got was talking about overall system defaults, concerning fontconfig rules therefore.

General idea was to weaken the word ‘default’ in regard to font setting by creating a direct window into basic fontconfig setting of the system (of course: for advanced effects, fontconfig xml coding is still needed).

For my convenience, YaST framework was used and new module called fonts had seen the light of the day not long ago. It is packaged as yast2-fonts in Tumbleweed and in my home for openSUSE 13.2.


I hope that, together with fontinfo.o.o, tuning your fonts will be much easier!

Certainly, this module is not done. Firstly, I would like to fix bugs which users will meet. After this stabilizing period, perhaps next hackweek, I will consider how hard would be to add per-user setting capability to fonts-config script, which would almost automatically mean per-user font setting capability in the module itself.


oSC15 – 200, Why not packaging workshop like mini hack sprint

January 17th, 2015 by

welcomeHello Geekos.

I’m contacting you personally, as an openSUSE Board member.

You certainly already know that we want to have a kicking openSUSE conference next 1st-4th May 2015 at the Haag (NL).

Thus I’ve found that creating special workshop organized by development project could foster our beloved distribution.

oSC is the unique case in the year, where Geekos from all around the world meet together.
Let’s imagine you, meeting perhaps for the first time your fellows, having nice discussions, and hacking around the software you maintain.
There’s high level of chance to meet also your end users, and have constructive exchanges.

That’s why I invite you to propose a workshop directly to our event tools:

Having a workshop run like a mini-hack sprint, would help any of us in the distribution and the project.
Be it like learn people how to submit nice package, how to do maintenance, or how to do bug triage.
I feel confident that you will have the creative approach to resolve your own problematic.
The event place has small rooms for unattended sessions and they could be used to extend your workshop to get some more work done.

Some practical aspects:
oSC website : https://events.opensuse.org/conference/oSC15

And soon the travel support program for oSC 15 will be opened to handle your request about getting financial support for going to oSC.

If you have any questions, thoughts or ideas, don’t hesitate to ask on -project mailing list
or ping me by reply.

A final note about the why you should do it? Well beside being one of our “heroes” even if nobody need them 🙂
You and your co-maintainers will be able to explain your “job” on the project.
Don’t you want to inspire new comers, lead them directly to the right direction, and share the load.
Meeting you there, will also help our “marketing” force to light up a bit the work done in the shadow.

I really will appreciate your presence, afterwards, it’s you that create our distribution.
The time has come for you to be warmly thank.

I’m looking forward to see you there.

another way to access a cloud VM’s VNC console

February 8th, 2014 by

If you have used a cloud, that was based on OpenStack, you will have seen the dashboard including a web-based VNC access using noVNC + WebSockets.
However, it was not possible to access this VNC directly (e.g. with my favourite gvncviewer from the gtk-vnc-tools package), because the actual compute nodes are hidden and accessing them would circumvent authentication, too.

I want this for the option to add an OpenStack-backend to openQA, my OS-autotesting framework, which emulates a user by using a few primitives: grabbing screenshots and typing keys (can be done through VNC), powering up a machine(=nova boot), inserting/ejecting an installation medium (=nova volume-attach / volume-detach).

To allow for this, I wrote a small perl script, that translates a TCP-connection into a WebSocket-connection.
It is installed like this
git clone https://github.com/bmwiedemann/connectionproxy.git
sudo /sbin/OneClickInstallUI http://multiymp.zq1.de/perl-Protocol-WebSocket?base=http://download.opensuse.org/repositories/devel:languages:perl

and is used like this
nova get-vnc-console $YOURINSTANCE novnc
perl wsconnectionproxy.pl --port 5942 --to http://cloud.example.com:6080/vnc_auto.html?token=73a3e035-cc28-49b4-9013-a9692671788e
gvncviewer localhost:42

I hope this neat code will be useful for other people and tasks as well and wish you a lot of fun with it.

Some technical details:

  • The code is able to handle multiple connections in a single thread using select.
  • HTTPS is not supported in the code, but likely could be done with stunnel.
  • WebSocket-code was written in 3h.
  • noVNC tokens expire after a few minutes.

Hackweek: Hot Chili Sauce for Hot Lizards

October 8th, 2013 by

This hot sauce can be used to spice up your food, give you creative
energy, and is a nice gift for your friends and family members — not
only for Hackweek.

Name: hot-chili-sauce
Summary: Toms’s Hot Chili Sauce
License: BSD
Version: 1.0
Group: Cooking/Sauce/Chili


New Raspberry Pi Image

September 7th, 2013 by

update: new image with kernel-3.6 and minimal X11/icewm http://www.zq1.de/~bernhard/linux/opensuse/raspberrypi-opensuse-20130911x.img.xz (103MB)

We got a new armv6 based image for the Raspberry Pi.
This one is only 82MB compressed, so pretty minimalistic.

The exciting new thing is that this was created using an alternative image building automatism which I wrote from scratch in three hours this morning.
The scripts can be found at
and are also embedded within the image under /home/abuild/rpmbuild/SOURCES/

This means that everyone can now easily build his own images the way he likes and even branch and do submit requests for changes that are useful for others.
The way to use this is simple.
If you have 6GB RAM, you can speed things up with export OSC_BUILD_ROOT=/dev/shm/arm before you do
osc co devel:ARM:Factory:Contrib:RaspberryPi altimagebuild
cd devel:ARM:Factory:Contrib:RaspberryPi/altimagebuild
bash -x main.sh

This pseudo-package does not easily build within OBS or osc alone because it needs root permissions for some of the steps (chroot, mknod, mount), which could only be workarounded with User-Mode-Linux or patching osc.
The build consists of three steps that can be seen in main.sh:

  1. First, osc build is used to pull in required packages and setup the armv6 rootfs.
  2. Second, mkrootfs.sh modifies a copy of the rootfs under .root to contain all required configs
  3. And finally, mkimage.sh takes the .root dir and creates a .img from it that can be booted

This can build an image from scatch in three minutes. And my Raspberry Pi booted successfully with it within 55 seconds.

There are some remaining open issues:

  • the repo key is initially untrusted
  • still uses old 3.1 kernel – solved
  • build scripts have no error handling

Compared to the old image, this one has some advantages:

  • It is easier to resize because the root partition is the last one
  • Compressed image is much smaller
  • Reproducible image build, so easy to customize
  • It is armv6 with floating point support, so could be faster
  • We have over 5200 successfully built packages from openSUSE:Factory:ARM
    so for example you can install a minimalistic graphical environment with zypper install xauth twm xorg-x11-server xinit and start it with startx

So if you wanted to play with openSUSE on RPi, you can do so right now and have a lot of fun.

GPIO on Raspberry Pi

March 31st, 2013 by

We have these working openSUSE Factory images for the Raspberry Pi, which is an ARM-based mini-computer, and since I want to encourage my kid to do more with computers than playing games (even if they are open-source), I looked into how GPIOs worked.
For that, you need to find the pin allocation – e.g.
in the elinux GPIO description or
has a video which has it explained at 03:00

For my test, I wired together pin11 and pin12, which are GPIO17 and GPIO18.
I wanted GPIO17 to receive what is sent by GPIO18.
This is how this looked for me: foto of GPIO17 and 18 wired together

Using it directly from the shell is simple:
echo 17 > /sys/class/gpio/export
echo 18 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio18/direction
echo 1 > /sys/class/gpio/gpio18/value
watch -n 1 head /sys/class/gpio/gpio*/value

If the wiring and configuration was right, the “watch” will show gpio17/value to become 1 too.
You can then also pull the wire (or insert a physical switch) and see gpio17/value dropping to 0 again, when it is no more receiving the current from the other pin.

If you managed to get this working, you reached level one of hardware-hackery.

A week in the Green Tail …

February 16th, 2013 by

Fosdem + Hackaton

Green Tail
As any hackaton, you finish a bit exhausted. but what the hell, how rich was this week!

I will not come back on the long (could we say impressive) list of things done.
Wiki Marketing
or Artwork todo.

A enormous thanks to all participants :
Carlos (victorck), Carlos (CarlosRibeiro), Izabel (IzabelleValverde), Kostas (warldofff), Ilias (zoumpis), Marcel (tux93), Richard (ilmehtar), Michal (|miska|).

Also they deserve a full bunch of applause, thanks to SUSE’s people!

Augustin, Jos, Will, Christopher, Adrian, Henne, Jurgen, Kenneth, Cassio, Alberto, Ralf, Roland, James, Jan, Ludwig, Cornelius, Suzanne and at least a big dozen of others…

For your clear engagement, your support to empower our community, your advises, your welcomes, and being so kind with the turbulent community’s Geekos we were…


Optimizing a boot time, aka 2 second boot

July 26th, 2012 by

During the hackweek, I have decided to take a look onto a boot process to realize, how fast can be boot of the system. This metric is considered as a not important, especially in a geek community. But I am sure that this is an important part of user experience. Following text is mean to share my investigations with you – but you should be aware what you are doing, since I have been focused on reducing the boot time as much as possible.

A bit of theory

Basically you have three possibilities how to make your boot fast.

  1. Start things in a parallel.
  2. Start things on demand.
  3. Start less things.

… root of all evil …

“Premature optimization is the root of all evil.”

And I will modestly extend Donald Knuth’s sentence, that the blind optimization as well. So if we have to optimize something, we have to know what to do. Fortunately systemd comes with an excellent tool called systemd-analyze, which show us our boot in several ways.

The simple run of command prints the time we spent in a boot and in which phase.

# systemd-analyze
Startup finished in 8480ms (kernel) + 30873ms (userspace) = 39353ms

That was the default (minimal X system) 12.2 installation on my EEE 701 netbook, which is probably not suitable to work as nowadays cellsmarphone, because is pathetically slow. On the other hand is it a perfect playground, so let’s continue with an investigating.

The overall time is nice, but won’t help to know what’s going on. There are two more subcommands, blame and plot shows us more information about the boot. The first shows the services sorted by the start time. The ones boots so long are those we should kicked off as a first ones.

Let see what slow the boot down a most

$ systemd-analyze blame | head
 11385ms network.service
  5664ms SuSEfirewall2_init.service
  5575ms systemd-vconsole-setup.service
  3032ms ntp.service
  2840ms remount-rootfs.service
  2230ms postfix.service
  2021ms network-remotefs.service
  1925ms cpufreq.service
  1661ms SuSEfirewall2_setup.service
  1506ms xdm.service

And take look at the output of systemd-analyze plot command

openSUSE 12.2 boot diagram

You can see, that there is a long chain of SuSEfirewall2_init -> network -> network-remotefs -> SuSEfirewall2_setup tooks several dozen seconds to be finished. And nothing is wrong with that, but that is the server solution, not what I want to have on my tiny laptop.

Making a laptop boot twice more faster

So having the complex dependencies of several services in mind, I decided to mask some of them. Masking in systemd world means the service cannot be started using systemd, so it becomes invisible for it. I masked those

  • network.service – will be replaced by NetworkManager, which is more suitable for laptops usage
  • SuSEfirewall2_init and SuSEfirewall2_setup – even if it’s a security feature, a risc for laptop, which is mostly offline and running only sshd is pretty small.
  • ntp.service, network-remotefs.service – those does not makes a sense on my laptop
  • postfix.service – I do not want to send emails via /usr/bin/sendmail
  • cpufreq.service – it is even not supported by my CPU (grep rc.cpufreq /var/log/messages)

Do not forget to install NetworkManager and the applet and change the /etc/sysconfig/network/config and reboot.

Now we have

$ systemd-analyze
Startup finished in 8528ms (kernel) + 11123ms (userspace) = 19652ms

Using an strace with systemd

Now we have a list of worse services

$ systemd-analyze blame | head -n 10
  5476ms xdm.service
  4172ms systemd-vconsole-setup.service
  3950ms systemd-modules-load.service
  2781ms remount-rootfs.service
  1848ms NetworkManager.service
  1439ms media.mount
  1426ms systemd-remount-api-vfs.service
  1419ms dev-hugepages.mount
  1411ms dev-mqueue.mount
  1371ms sys-kernel-debug.mount

and a proper boot chart

bootchart w/o network.service

It shows us an another botleneck, which is the systemd-vconsole-setup.service, because it delay the sysinit.target, which is very early boot stage. In case like this, we can only use strace to know, what is taking too long. And debugging is pretty straightforward in systemd world. All we have to do is copy service file to /etc/systemd/system and change the ExecStart

ExecStart=/usr/bin/strace -f -tt -o /run/%N.strace /lib/systemd/systemd-vconsole-setup

and reboot. Then you will find the output in /run/systemd-vconsole-setup.strace with a timestamps. Looking there it’s obvious calling hwinfo --bios is extremely expensive in this stage. You can speedup the unit by setting the KBD_NUMLOCK to yes or no in /etc/sysconfig/keyboard, or you can try to mask it completely I did.

The next service needs to closer look was system-modules-load – then strace says that it spent 2(!) in init_module() for module microcode. I disabled it as well, even for CPUs needs it can’t be recommended.

Native systemd units

There is one tiny init script called purge-kernels, which starts for 300ms according blame. And in this particular case systemd alternative will be way more effective

$ cat /etc/systemd/system/purge-kernels.service
Description=Purge old kernels


because systemd only do one stat on the file and do not run it at all, so this service disappears from the blame at all.

The kernel time

There is one interesting thing about kernel time – 8 seconds spent there seems to be a lot to me. Simple ls on /boot gave me a pointer

$ ls -lh /boot/vmlinuz-* /boot/initrd-*
-rw-r--r-- 1 root root  14M Jul 24 11:03 /boot/initrd-3.4.4-1.1-desktop
-rw-r--r-- 1 root root 4.7M Jul 10 15:48 /boot/vmlinuz-3.4.4-1.1-desktop

The initrd is huge, around three times bigger than kernel? So let’s try to find what caused that. Every package can add it’s own setup script into /lib/mkinitrd/scripts/ thus let ask rpm whose did that

$ rpm -qf /lib/mkinitrd/scripts/setup-* | sort -u

So I went through a list and try to uninstall things I do not need

  • cifs-utils – if you do not have any windows disc to mount, you can remove, but no impact on initrd size
  • cryptsetup – this is a popular service for laptops, but I do not have any luks device, so let skip that. It removes a half of Yast as well, so I saved 18M of space, but a little in initrd.
  • device-mapper, dmraid, kpartx and lvm2 – cannot be easily removed as too much low-level stuff depends on it
  • mdadm – no linux md devides, skip that
  • mkinitrd – removal can reduce initrd to zero, but we would need own kernel
  • multipath-tools – no multipath device, let skip that

  • plymouth-scripts – who would need the “fancy” boot when booting so fast? – reducing initrd to 8.9M
  • splashy – the same – and reducing initrd to 6.6M

So the things intended to provide fancy boot actually bloats the system. Let’s measure the impact of those changes

$ systemd-analyze
2781ms (kernel) + 4999ms (userspace) = 7780ms

bootchart w/o network.service

And that’s all folks …?

There are a lot of factors slowing our boot – reducing it to 8 seconds is not that bad. One have to go carefully through blame and plot output to see what delays his computer in start. I would say making NetworkManager default one at least when installing laptop pattern would be nice and simple change as well as continue on “systemdifization” of openSUSE.

There are few other tricks, which get us closer to the target time, but I’ll post them next day.

Snapper and LVM thin-provisioned Snapshots

July 25th, 2012 by

SUSEs Hackweek 8 allowed me to implement support for LVM thin-provisioned snapshots in snapper. Since thin-provisioned snapshots themself are new I will shortly show their usage.

Unfortunately openSUSE 12.2 RC1 does not include LVM tools with thin-provisioning so you have to compile them on your own. First install the thin-provisioning-tools. Then install LVM with thin-provisioning enabled (configure option –with-thin=internal).

To setup LVM we first have to create a volume group either using the LVM tools or YaST. I assume it’s named test. Then we create a storage pool with 3GB space.

  # modprobe dm-thin-pool
  # lvcreate --thin test/pool --size 3G

Now we can create a thin-provisioned logical volume named thin with a size of 5GB. The size can be larger than the pool since data is only allocated from the pool when needed.

  # lvcreate --thin test/pool --virtualsize 5G --name thin

  # mkfs.ext4 /dev/test/thin
  # mkdir /thin
  # mount /dev/test/thin /thin

Finally we can create a snapshot from the logical volume.

  # lvcreate --snapshot --name thin-snap1 /dev/test/thin

  # mkdir /thin-snapshot
  # mount /dev/test/thin-snap1 /thin-snapshot

Space for the snapshot is also allocated from the pool when needed. The command lvs gives an overview of the allocated space.

  # lvs
  LV         VG   Attr     LSize Pool Origin Data%  Move Log Copy%  Convert
  pool       test twi-a-tz 3.00g               4.24
  thin       test Vwi-aotz 5.00g pool          2.54
  thin-snap1 test Vwi-a-tz 5.00g pool thin     2.54

After installing snapper version 0.0.12 or later we can create a config for the logical volume thin.

  # snapper -c thin create-config --fstype="lvm(ext4)" /thin

As a simple test we can create a new file and see that snapper detects its creation.

  # snapper -c thin create --command "touch /thin/lenny"

  # snapper -c thin list
  Type   | # | Pre # | Date                          | Cleanup | Description | Userdata
  single | 0 |       |                               |         | current     |
  pre    | 1 |       | Tue 24 Jul 2012 15:49:51 CEST |         |             |
  post   | 2 | 1     | Tue 24 Jul 2012 15:49:51 CEST |         |             |

  # snapper -c thin status 1..2
  +... /thin/lenny

So now you can use snapper even if you don’t trust btrfs. Feedback is welcomed.


January 28th, 2011 by

Arts, buffer, check, clutter, cobbler, colorblind, concurrent, convert, cook, crash, dialog, dump, expect, file, folks, fortune, genius, global, hello, indent, less, links, meanwhile, mirror, screen, sparse, suck, tree, units, words. What do these ordinary English words have in common? They are also names of software projects, which becomes a problem if you want to recognize package names in text. I understand that in the old days, the name of a command or application was only relevant in the context of the computer it ran on, and file names had to be short. Some of these names have allowed for a variety of jokes. But why, in the age of portable programs, WWW and search engines, can’t people come up with less ambiguous names? I mean, it’s not hard to join two words, or, at a minimum, prefix a word with a vowel, like, uhm, a round fruit does. 🙂

Oh, and did I mention that we have over 160 packages with a 2-3 letter name? The one mentioned in the title is a programming language, btw.