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Tue, 20 Aug 2013

Mapping the research literature

Paperscape visualizes all the arXiv papers. The arXiv is a pioneer in Open Data publishing from 1991 and started by Paul Ginsparg for high energy physicists (hep). It soon extended to most physicists.

According to it's importance (citation) each paper has a certain radius and the citations also link the papers to their position in the map. In addition there are helpful overall topics and one can click once zoomed in on each paper to know all the authors and the title. The colors correspond to each arXiv section.

[/phys] permanent link

Thu, 21 Mar 2013

Gnome shell weather extension

Noticed with a lot of happiness today that Gnome extensions list a new one showing weather information. (:

[/info] permanent link

Fri, 08 Mar 2013

Wrong moves
A bizarre closed user-tracking schism is rebased from shaky grounds to an unexisting target. It is sad to see this continous decline due to unchallenged decisions.

[/tech] permanent link

Sun, 21 Oct 2012

Quantum physics basics II

The words "quantum leap" lead to the second misconception that changes of said physical system are instantaneous, which is obviously wrong.

Unnamed ten year Debian dude, please take a physics 101: The photon of the LASER comes from a stimulated emission, which is a transition between different states.

[/phys] permanent link

Sat, 20 Oct 2012

Basic understanding^Wmisconception of quantum physics

According to the release manager of Ubuntu the 10.12 release features the most minimal improvements: ''Doing is a quantum leap from imagining.``

Anyone having a minimal quantum physics exposure should be aware that a quantum leap is a very tiny leap. So according to the paraphrased intro this release should not even contain 'stable` updates?!

[/phys] permanent link

Fri, 05 Oct 2012

New klibc release 2.0.2

The new klibc features fixes for latest 3.6 Linux, dash sync and arm fixes. For details see the longer story on: klibc 2.0.2 release announcement or klibc git repository.

[/tech] permanent link

Mon, 11 Jun 2012

1.5M CPU hours in 2012

1.5M CPU hours runs on the Vienna Scientific Cluster by my 3D+3V hard expanding loops code. It is simulating the Chromo-Weibel instability of a non-Abelian plasma in an 1d expanding background to account for the expansion of a Quark-Gluon plasma fireball in a heavy ion collision. The code is parallellised using Open MPI and one single run roughly needs 0.5TB memory to hold all the needed 5-dimensional matrices and ~ 72h to complete. The resulting heavy operation is of course matrix multiplication of those physical and auxilliary fields.

I tried to use git-annex on the resulting physical fields data output of ~ 150Gb and 300k files. Currently I do prefer git itself for it's speed and it only doubles the amounted space. I'm thrilled to see that git annex is still considering this "semi-extreme" usecase of lots of data files as it would help collaborators to have partial checkouts for laptop usage and quick checks. As the git-annex kickstarter is a rocket, i'd add my wish to see the current symlink mess go: desymlink git-annex.

Now it is the time to properly analyse all this data and get the full 3d paper follow up on Instabilities of an anisotropically expanding non-Abelian plasma: 1D+3V discretized hard-loop simulations (previous paper) out maybe soon. (;

[/phys] permanent link

Thu, 31 May 2012

New klibc release 2.0

The new klibc features prominently the merged stdio branch (causing the version bump). The buffered I/0 allows a faster fstype and thus faster boot. Plus klibc gained the support of several stream I/O functions, for details see the longer story on: klibc 2.0 release announcement or klibc git repository.

The dhcp cmd ipconfig can now generate enough info for a proper lease file too and got fixed concerning the min length of it's replies. Google sponsored the /etc/fstab or cmdline boot mounting in kinit.

2.0 is shipping several arch fixes including i386 signal fixes, m68 support, s390x, sh4 compile fixes. There is still portability work todo: #439181 ia64 shared lib buggy (longdated unresolved ia64 mystery), #634890 amrhf all binaries segfault (maybe signal related), status on parisc is unknown, avr32 patch is untested (might as well just merge) and sh4 SIGILL. We got nice arch testcoverage thanks to mksh testsuite and working mksh klibc support. We are confident of this release on all this archs: alpha, armel, m68k, mips, ppc, ppc64, sparc, s390, s390x and x86. (:

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Sun, 06 May 2012

Gnome shell rocks

The Gnome shell is a great step. Finally the Linux default Desktop is not only useful (as Gnome 2.X used to be), but also stylish and modern. It's a different kind of desktop, which seems to irk desktop habits of some peoples. I'm proud to show it off. This happened for the last time years ago while doing some funny config quirks of fvwm. Gnome 3.x is cool. (: Also the customisability via all the extensions is fun.

What I do miss is the gnome weather (There used to be an incarnation with plenty of geographical sites, which got somehow got axed later.) and more packaged extensions for out of the box deployments (wish #661782).

I seem to be too lunatic to find session settings in "System Settings" for having startup applications run or the used applications reopened (please yes evince show the same pdfs).

The other minor critic is that "System Settings" is quite empty, but has on each system a funny advertisement for "Wacom Tablets". Ah and after a myriad of suspends and network-manager stops/restarts gnome-shell likes to segfault, which is no nuisance as it restarts.

[/tech] permanent link

Mon, 02 Jan 2012

CPhT visit automn 2011

On my new particle physics blog (yupie to ikiwiki, thanks joey) posted some recollection of a fine, productive and busy Paris research visit to the Ecole Polytechnique.

The feed agregegator for particle physics blogs got relaunched too that automn. In case you are interested in particle physics this should keep any reader updated on the Higgs hunt, black holes searches, fundamental interactions and much more.

[/personal] permanent link

Thu, 20 Oct 2011

New meme: OS of your president web presence

Let's start that a new meme on planet, haven't seen one for a while. The Austrian president starts the relaunched web presence with a "Putin" style parachute jump.

 lynx -dump -head http://www.bundespraesident.at/ 
HTTP/1.1 200 OK
Date: Thu, 20 Oct 2011 08:42:35 GMT
Server: Apache/2.2.16 (Debian)
X-Powered-By: PHP/5.3.3-7+squeeze3

So apparently the used typo3 installation is newer, but the used OS for the Austrian presidential web site is: Debian Squeeze.

[/propaganda] permanent link

Tue, 20 Sep 2011

Recurring Maxima failures

Every once in a while I try out latest Debian/sid Maxima as it sees continuous development: Maxima git repo.

Todays failure is an integral given at the Bloc course "Aspects of QCD at Finite Density". It is an exercise to calculate following simple integral that should just give a Bessel function:

(%i3) integrate(exp(z*cos(t))*cos(a*t), t, 0, %pi);
                           %pi
                          /
                          [               cos(t) z
(%o3)                     I    cos(a t) %e         dt
                          ]
                          /
                           0

As usual the result it returns is the integral itself.. :/ So yes indeed Maxima is nice for simple undergrads calculation: Maximum Calculus with Maxima, but unfortunately don't expect much for more complex problems. The result is the partition function of the chiral perturbation theory in the simple setup of equal quark masses and one quark flavour family. Sadly Integrals returning Bessel functions seem to regularly fail.

[/phys] permanent link

Tue, 23 Aug 2011

klibc 1.5.25 release

Mike Waychison from Google sent fancy costum tailored enhancements to kinit. Thanks to new klibc capget and capset support kinit now understands "drop_capabilities=" bootparam. It specifies a list of capability names that will be dropped before switching over to init. dirent.h saw the addition of scandir() and alphasort(). Gentoo devs pushed a klcc enhancement. For details see klibc 1.5.25 release annoucement.

A lot of stuff is in work: current klibc patch queue.

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Wed, 27 Jul 2011

klibc release 1.5.24

Good pile of fixes made it worth to release current klibc git master. Patches came from Gentoo, Google and Openembedded. For details see klibc 1.5.24 release announcement.
Forgot somehow to announce the previous klibc 1.5.23 dash sync release and containing Ubuntu arm+ppc64 porter fixes.

[/tech] permanent link

Mon, 13 Jun 2011

Easy way to void() your Debian support

Craig Small gives a very bad advice on his recent post Debian Linux on HP DV6-6023TX. As soon as one loads such a binary graphics driver your Linux kernel is marked as tainted. Due to be running a proprietary module your box may behave strangely and is certainly not debuggable. Be aware that in such a case you are no longer running a free and open OS.

What he actually wants is a very recent 3.0 linux image from experimental and to google for vga switcheroo, which leads to the following commit with explanations for /sys/kernel/debug/vgaswitcheroo/switch: vga_switcheroo: initial implementation (v15).

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Wed, 18 May 2011

klibc 1.5.22 release

This release has several ipconfig (klibc dhclient) enhancements, arm porting fixes and usual cleanups: For details see klibc 1.5.22 release announcements or klibc git.

[/tech] permanent link

Fri, 13 May 2011

initramfs-tools release 0.99 "scarpe rotte e pur bisogna andar"

This new release features /run usage and xz support. For the details see the release announcement of latest initramfs-tools. The upload itself fixes 18 (19) bugs in the Debian BTS and has also a cute lilo support patch hiding under "initramfs-tools: Fix handling of numeric root= arguments to be udev-friendly" coming from Ubuntu. (; Ben Hutchings revamped the bootloader linux-2.6 hooks in order that update-initramfs no longer calls any bootloader by itself. Thank you for all the contributions. The development docs got nicely refreshed too.

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Wed, 02 Mar 2011

Cross distribution collaboration on longterm 2.6.32 linux-2.6

I'll collect here links to the various linux-2.6 distribution trees based on the longterm release 2.6.32. I won't go into details of bigger external patches (grsec, openvz, rt, xen, ..), which in consequence also aligned themselves on 2.6.32.

Important bug fixes usually are connected to some bug report, which may be publicly viewable. So from the patch and changelog entry one can usually assume if a certain patch satisfies the stable criteria and forward it for 2.6.32 longterm inclusion (+ other branches where it might apply). If the patch applies and compiles fine with the Debian tree one can assume that the patch will be fine for upstream 2.6.32 as Debian with small exceptions mostly follows the longterm release: 2.6.32 branch of Debian linux-2.6 (Comment: This is currently only a svn mirror but this bug is worked on for next release).

The canonical 2.6.32 linux-2.6 longterm repository is of course on kernel.org maintained by gregkh. Opensuse publishes it's kernel-source on gitorious including all branches and the especially interesting SLE11-SP1 2.6.32 branch. Fedora was following till late Autumn 2.6.32 and the F12 branch has the relevant patches. Ubuntu released 10.04 with 2.6.32 as in a collaborative decision they also based their drm on 2.6.33 (same story as in Debian, thus particularly relevant for us). Oracle had a 2.6.32 that was maintained until Sept 2010 or such.

It is already bad that kernel source in Red Hat doesn't really follow upstream 2.6.32 longterm release itself. For 2.6.18 of course no such option existed, but for 2.6.32 this policy already shows a certain snobbery. Red Hat 6.0 Beta at least shipped kernel-2.6.32-37.el6.src.rpm with broken out patches - since then no patch series or git tree to be seen from RH. This strange move got since picked by lwn - RH "obfuscated" kernel source.

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Wed, 26 Jan 2011

klibc 1.5.21 release

This release is "slightly" delayed due to lots of physics calculations for my final PhD year at the TU Vienna with all fixes that piled up since last summer: Support for newer GNU make 3.82, x86_32 signal fun, the self explantory KBUILD_REPRODUCIBLE and various cleanups: For details see klibc 1.5.21 release announcements or klibc git.

[/tech] permanent link

Mon, 13 Dec 2010

CUPS Printer foo

I seem to have a sweet spot for having troubles with printers in stressy times. For restarting a stopped specific queue under CUPS it is easiest to specify:

 cupsenable <queuename>

The symmetric command for stopping is cupsdisable.

[/tech] permanent link

Tue, 02 Nov 2010

"We'll Always Have Paris" linux-2.6

At the mini-DebConf Paris 2010 the Debian linux-2.6 team released latest 2.6.32-27 adding stable 2.6.32.25 plus security fixes and drm/intel fixes from the Ubuntu shared drm 2.6.33 tree.

Beside the productive Debian kernel team meeting, whose minutes will be forthcoming, the mini Debconf had a great welcoming setup and friendly chats. We enjoyed an impulsive Saturday evening at Chatelet in middle of the funny Parisian Halloween mess.
Update: Photo of the last busy meeting session during lunch break that allowed us to finalise all Paris meeting topics.

[/kernel] permanent link

Wed, 01 Sep 2010

fjp

Frans Pop contributions to Debian has already been honoured: Frans Pop obituary by Steve McIntyre. One less known fact is that he hacked in upstream linux-2.6 too. Latest linux-2.6 git lists him with 80 commits. A bigger part of his work was testing latest linux-2.6 on different architectures. There are lots of patches with "Reported-by: Frans Pop " and "Tested-by: Frans Pop ". Also in this field he was aiming for big coverage and a special responsive tester.

I am very sad to have missed the opportunity to meet you in person. You are missed. Rest in peace, my friend.

[/personal] permanent link

Sat, 28 Aug 2010

Release of klibc-1.5.20

This release fixes an important ipconfig regression from Lenny due to a badly tested monster patch 4efbcf90f60. ipconfig should now perform better then ever, thanks to the inflow of fixes since Lenny release. This RC fixes are scheduled for Squeeze and it already landed in Sid.

1.5.19 had no release announcement, but fixed compilation on x86_32, the syscall handling on sh4 (initramfs-tools is said to boot fine with it), valgrind ipconfig warnings and added getrusage() for the mksh port.

Thanks to hpa for giving me the official co-maintenance of klibc. Thanks to all contributors.

P.S.: See klibc git repo.

[/tech] permanent link

Thu, 26 Aug 2010

Coffee is better without sugar

Apparently this statements also holds true for frozen yogurt. An Austrian A1 spokes person has confirmed that the HTC Magic will not receive a 2.1 or 2.2 Android update. One can only wonder about the sugar HTC puts on top of regular Android that hinders themself to update their products. The Austrian A1 carrier sells you the device for a 18 month contract, but actively only supported it for 6 month. I must revise my previous positive review of the HTC Magic.

Some HTC speaker had promised earlier this year an upgrade to at least 2.1: HTC Magic 2.1 upgrade. A SFR speaker had promised an update to current Android: HTC Magic and Nexus One 2.2 upgrade.

The Webkit Android Browser can be easily tricked into leaking your user and passwords: Android Luecke. Beside the obvious that as a user one shouldn't give out to much data to untrusted third party this opens lots of Google accounts for criminal activity. The inability of the carrier to provide a secure and uptodate device is massively deceiving and certainly not appropriate handling of their defects liability.

[/info] permanent link

Wed, 21 Jul 2010

Solid bases in Theoretical Physics

Landau, L. D.; Lifshitz, E. M. (1976). Course of Theoretical Physics is still the most interesting and solid base that is to be considered as a reference and inspiration in Theoretical Physics.

The reference for "Classical Electrodynamics" is the book by J.D. Jackson. "Advanced Quantum Mechanics" by J.J. Sakurai is a popular student choice. Compendium of Relations contains various formulas and relations of the Standard Model. The Lecture Notes on General Relativity by S. Carroll are a solid introduction for an initiate relativist. "Quantum Field Theory in a Nutshell" by A. Zee is amazing. Quantum electrodynamics can be explored in the books by "The Quantum Theory of Fields" by S. Weinberg or "Quantum field theory" by L.H. Ryder or Quantum Chromodynamics in M.E. Peskin & D.V. Schroeder "An Introduction to Quantum Field Theory". The lecture notes on Quantum Chromodynamics (QCD) might be interesting for people diving into the particle physics standard model. "Finite-temperature field theory: Principles and Application" discusses systems in equilibrium but at finite temperatures and chemical potentials and thus connects to cosmology of the early universe.

The field of Statistical Field Theory has the classic "Quantum Many-Particle Systems" by J.W. Negele and H. Orland or the more recent "Quantum Field Theory of Many-Body Systems" by X-G. Wen or "Ultracold Quantum Fields" by H.T.C Stoof, D.B.M. Dickerscheid, K. Gubbels.

String Theory is so diverse that you'll find lots of different approaches, recommendations are Graduate Course in String Theory by A. Uranga, Applied Conformal Field Theory by P. Ginsparg, Lectures on String Theory by D. Tong or more introductory the book "A First Course in String Theory " by B. Zwiebach or the dense "Superstring Theory" by M. Green, J. Schwarz and E. Witten, "String Theory" by J. Polchinski. "Quantum Field Theory of Point Particles and Strings" by B. Hatfield assumes no previous stringy background and is known for excellent explanation of the path integral formalism. M. Nakahara wrote the wonderfull bridge to maths: "Geometry, Topology and Physics".

So please when looking for "references" in theoretical physics venture on solid grounds and don't get distracted by sketchy notes.

Update: Peter West pointed out that the The Feynman Lectures on Physics are missing as a timeless reference.

[/phys] permanent link

Thu, 22 Apr 2010

Fresh klibc 1.5.18 release

The overdue dash sync from 0.5.3 took a month to be done, but now klibc is shipping newer dash 0.5.6 then actual unstable dash.

Fixes for this release include fstype support for btrfs and ext4 without journal. Moving README's around so that they can be shipped for avid readers: README.ipconfig go :) The goodie from this time is the sh4 build fix form the very active Debian sh4 porters. ipconfig, nfsmount and kinit have now simpler DEBUG build. ipconfig build warnings got shot by a Google patch.

If your patch hasn't made it yet, please ping me for next queue: klibc git repo, Unofficial patch queue.

P.S.: Ubuntu Lucid pushes out klibc 1.5.17 thanks to Colin Watson.

[/tech] permanent link

Tue, 06 Apr 2010

"Little Bang" 0.94 initramfs-tools release

Heavy Ion collisions try to recreate conditions very shortly after the Big Bang. Thus the created quark gluon plasma is often the Little Bang, due to recreating this very hot conditions.
The kernel Team already uploaded the linux-2.6 Big Bang release now follows initramfs-tools with the Little Bang. ;-)

Newer initramfs comes with lots of fixes and new features:

  • Faster boot thanks to Ubuntu merged patches using pre-cached boot scripts. It be cool if someone could time that and let us know?
  • Support for several compression schemes as set in initramfs.conf or overridden by appropriate mkinitramfs call.
  • Better MODULES=dep support /sys parsing (Still needs fixes for md).
  • Hooks for out of linux-2.6 make deb-pkg generated linux-images.
  • Call ipconfig with increasing timeouts to better fit with large scale clusters.
  • Use BOOTIF mac address passed from gpxe in setup_networking.
  • Out of the box support for devtmpfs. Hurra for devfs 2.0.
  • Loading of the netconsole module together with the specified args, when netconsole is set as bootarg.
  • Adds available, built network drivers in a dynamic way without need of hardcoded list.
  • Smaller and thus faster MODULES=most generated initramfs due to kicking the video drivers out of generic initramfs.
  • Last but not least don't suppress eventual modprobe errors.

Thanks for all the patches and useful input! Sorry for late release, will try to do it earlier more often and there is hope of an Ubuntu sync: view of initramfs-tools repo.
P.S.: cryptsetup needs fixup of #576488, udev can now start at a earlier stage of initramfs.

[/kernel] permanent link

Sat, 20 Mar 2010

New klibc release 1.5.17

Not only fixes ipconfig regressions due to fixes in 1.5.16, but ipconfig should no longer discard useful packages. We also fixed a long standing klibc sparc specific socket bug (#444087): sparc lists socket system calls, but does not provide all of them natively. So one is better off on sparc to use sys_socketcall.

Thanks to Jan Hauke Rahm the packaging switched to modern Source Format 3.0 (quilt) with debhelper 7 usage reducing cdbs overhead on build. This is a big switch and makes me very happy.

New addition include a $(make help) target in Makefile to ease klibc build. A small losetup got added to klibc-utils.

i386 and sparc build fine against current linux-libc-dev: klibc-1.5.17 released
P.S.: New outfall seem to include armel and s390 due to libgcc changes.
Update: Seems only a small packaging error due to test target invocation, should be fixed in 1.5.17-3.

[/tech] permanent link

Mon, 15 Mar 2010

New release klibc 1.5.16 uploaded

The upload reduced RC count by one as klibc builds against recent linux-libc-dev including 2.6.34-rc1. Also libklic-dev uses them directly once installed thanks to a patch from Ben Hutchings. The klibc build saw several fixes from a big and refined Google patch queue.

The klibc-utils mount grew several useful features and ipconfig saw lots of bug fixes (send requested optional hostname, raise field length for rootpath DHCP option, ..): hpa klibc 1.5.16 release announce, Git klibc repo.

Update: According to build log there is still work todo for i386 and sparc. :)

[/tech] permanent link

Wed, 03 Mar 2010

2.6.32 sid updated and 2.6.33 in experimental

Experimental 2.6.33 will do the switch to UUID based root args, if you haven't switched already. Please test it out and report bugs on it, before we add the libata switch to squeeze 2.6.32.

2.6.32-9 includes 2.6.32.9 and several other fixes. For the following 2.6.32-10 Ben Hutchings pulled in newer drm for lots of intel fixes: Status of kernel X drivers. It also features radeon and nouveau KMS modules. Current 2.6.32 is stabilizing well and we are seeing lots of external patches lining up.

Update: Sorry due to jet lag got aboves version number wrong. You might want also to checkout: The season I have mostly been building kernels.

[/kernel] permanent link

Thu, 03 Dec 2009

Vienna buying Office Licenses

When you just read the following sentence: "usage of a software, that can only be used together with the Internet Explorer". You already know the consequence that several hundreds Wienux boxes are gone.
Heavily disgusted by the waste of community money.

The online local newspaper has a comment that seems quite to the point to me: "If as sysadmin you introduce Linux you'll be accounted for eventual failures, while with softies people just accept the shortcomings and won't blame you."
German source: Wiener Inkompetenz in IT Managment.

P.S.: Wienux got setup by inexerienced people having no prior exposure to Open Source. The project setup included a calculated failure from the start.

[/info] permanent link

Tue, 27 Oct 2009

HTC Magic 90 days Android usage

I love the fact that phones are ready to get a decent OS. I bought the phone for better connectivity and to get GPS goodness. 90 days later seems a good time to review the pros and cons:

    Pros:
  • The phone sees updates (Android 1.6 has recent 2.6.29 build with much nicer battery status and search box).
  • Easy to pick google calender together with useful gmail integration.
  • Often use the phone for a quick websearch (cinema programs on the run, news, shop opening times, ..) - to lazy to power up real laptop.
  • The touchscreen interface isn't too bad, but missed the nice resize effect seen on other touchscreens OS.
  • Connectbot is a half decent ssh client.
  • The consumed data is very low - never managed to touch the 1GB download bandwith limit.
  • gmaps is fun to look up and helpful in finding directions.
  • Last but not least important phone functions as easy dialing and good voice transmission are working.
    Cons:
  • The worst omission is a decent pdf reader. No way to read latest papers on arXiv.org.
  • The next big missing thing that worked since years with mobile phones is bluetooth file sending and receiving out of the box.
  • A more minor bugger - but still quite annoying: contacts sent to you as vCard don't get easily imported in contacts.
  • The camera from the HTC magic is not really pleasant.

Of course Android still seems like an alien sandboxed Linux, but I must say that the average usage capability of the mobile phone is very nicely enhanced.

P.S. Using allmost daily also Google Talk, Ultimate Stopwatch & Timer, Finance, GPS Status and the ultra cool Google Sky Map.

[/tech] permanent link

Wed, 21 Oct 2009

Particle Physics Planet

planet.teilchen.at is a shiny new selected blog roll of prominent Particle Physics blogs. Reading it should keep you updated on progress at the Large Hadron Collider (LHC) as well as on new discoveries in High Energy Physics, Astrophysics, Cosmology, advances in Quantum Chromodynamics (QCD), String Theory, Black Holes and many other hot physics topics. Most posts should be readable for scientifically interested public. Enjoy a daily read.

www.teilchen.at is the Austrian outreach site of Austrian particle and nuclear physicists. Authors are leading austrian scientists. The site just got relaunched with new features including some socialweb goodies (planet, share links on the bottom, better readability, noframes, ..). Happy if you send corrections or suggestions to mattems@teilchen.at.

[/info] permanent link

Tue, 20 Oct 2009

Debian Kernel Meeting

Vincent Sanders took notes during all our meetings at the Portland Linux Plumbers Conference: Debian Kernel Group Meeting. The condensed form has been posted today as Bits from the kernel team.

In the case of feedback I'd highly recommend to bring the Debian Kernel Mailinglist into the loop. The meeting decisions were done by the team as entity.

Responding to the deprecation of some external patches (Vserver, Xen Dom0): None of above patches have an upstream that supported the Lenny released version. Both have troublesome bugs in Lenny and thus are not in a condition one would expect from a stable release. If you want to help and have continued release of those beyond squeeze the answer is easy: Get them merged upstream. Openvz supports Lenny linux-2.6 version actively and promised to keep up with their work for Squeeze.

It has been a very productive meeting with lots of problems^Witems discussed. Interesting tracks for better cooperation between distributions, heavy technical tracks and loud BOFS. Quite some work has already been picked up since (Bug scripts, 2.6.31 experimental uploads, DEB_BUILD_OPTIONS=parallel=N support, package descriptions improvements, piuparts install fix, DFSG firmware clean, preempt, ..). So thanks a lot to Steve McIntyre (Debian Project Leader) for pushing the meeting, to Steve Langasek for setting it up on site and of course to everyone who contributed. Read aboves report for the full picture. :-)

[/kernel] permanent link

Tue, 24 Mar 2009

2.6.29 in sid

Latest Tasmanian Devil Linux 2.6.29 adds quite a lot of new features: Kernelnewbies 2.6.29 Overview.

Thanks a lot to the FTP Master Team for making possible the same day upload. Big thanks also for the regular testers of the rcX trunk snapshots.

[/kernel] permanent link

Mon, 09 Mar 2009

git: Throw away first X commits of a repository

Today got asked by a colleague, who wanted to throw away the early history of his repo. git allows you easily to rewrite the history start with:

echo $FIRST_SHA >> .git/info/graft
git filter-branch -f

Then with interactive git rebase you can rewrite this important initial commit. Of course you have to define $FIRST_SHA and your repo shouldn't be dirty.

[/tech] permanent link

Thu, 05 Feb 2009

initramfs-tools new Lenny features

initramfs-tools design principle is to ship a generic initramfs. The design explicitly allows lots of customization through hook and boot scripts. A previous post focused on the history of initramfs-tools. Several contributors enhanced initramfs-tools since the Debian Etch release so the non exclusive new feature list:

  • The initramfs contains all drivers/{ata,block,ide,mmc,scsi} modules instead of a stupid hard coded list. This gives bonus points for getting more future proof.
  • Configurable small initramfs: The MODULES=dep mode walks /sys/ for the needed drivers of the specific box. This was the most wanted feature and is the new default for some Debian-Installer embedded architectures. The code seems in between well tested even if some corner cases might still emerge. The smaller initramfs is needed for specific bootloaders and helps on slow target boxes.
    For a even smaller initramfs you can kick busybox if you don't have an lvm2 root or don't need it's debugging tools.
  • Quicker initramfs build: The update-initramfs command uses dpkg trigger and thus not every postinst update-initramfs(8) call leads to a new initramfs build. Also the build time got improved.
  • Improved panic message (yes users need to be handhold at this point :).
  • Potential debug log is visible after call to init(8) inside /dev/.initramfs/.
  • update-initramfs got hardened against failure on update or ro partitons.
  • The klibc utilities got worked on: chroot, fstype, ipconfig, mount, nfsmount sync.
  • Fixed various bugs in NFS and networking setup due to incorrect option parsing.
  • Allow to blacklist modules on boot by cmdline bootarg blacklist=modulename.
  • Allow non root usage of mkinitramfs.

As bonus to some cleanup and docs update we have also seen a Ubuntu sync and are not too diverged.

[/kernel] permanent link

Fri, 19 Sep 2008

playlist sept. 2008
This time crushing for goooood voices across really different styles:

  • Agoria - Think Different
  • Ellen Allien - Rej (Feat. Ame)
  • Trentemøller - Moan (Trentemøller Vocal Remix)
  • DJ Brace - slammed preview
  • p.tah - rasterpunkt
  • Spiral Tribe - Breach The Peace
  • Larry Heard presents Mr. White - The Sun Can't
  • Groove Armada - But i feel good
  • Modeselektor - The White Flash (Trentemøller Remix)
  • Mono & Nikitaman - Fresse Halten - Selber Machen

double *bounce* triple *bounce*
For the youngsters among you who missed out Spiral Tribe there tunes still kick ass. Mono & Nikitaman were the best at the Viennese Donauinselfestival and should be seeeen life. Only the Dj Brace track is not yet released. p.tah is the mastermind of B Seiten Sound. Enjoy ;)

[/personal] permanent link

Tue, 22 Jul 2008

OpenVZ Debian Linux images

Thanks to the Virtuzzo developers for forward porting the OpenVZ patch to 2.6.26. It uses a lot of the already merged namespace features (For interested peoples linux-next carries interesting sysfs patches). The openvz upstream merge statistic is impressive.

The namespace solution allows low overhead, while still running multiple Linux distributions in individual containers on the same box. Control over the network vitalisation is gained as a resource management for CPU power, I/O bandwidth and disk space. Live migration including snapshotting is possible too.

The Debian 2.6.26 Linux images will feature not only better Xen vitalisation support, kvm port to new archs, but also an opvenvz flavour. Please don't forget to install proper vzctl userspace support as the correct dependencies have not yet been added. Supported archs will start with both x86 and the ia64 archs. Tomorrows linux-2.6 Debian trunk snapshots will already build openvz. Thanks for your feedback.

P.S.: 2.6.26 is the targeted kernel for Lenny, we hope to convince Debian installer people to pick it up soonest - 2.6.25 is a not so bad backup plan as release hasn't fully approved 2.6.26 before extensive unstable testing.

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Wed, 25 Jun 2008

Open Source Graphic Drivers - oops less often

If you haven't read yet: Linux Graphics, a Tale of Three Drivers. The hard data is based on reports thanks to kerneloops.org. It matches quite evenly our bug experience on the Debian Linux images. As already stated "Open Source Graphic Drivers - They don't kill kittens". The unnamed company claims no need for open drivers.

Hardware vendors need not to forget that they don't get revenues from the drivers side. The conclusion is to buy hardware, where the vendor cares about Linux support. That means documents the hardware and enhances current free xorg with all needed goodies of enhanced power support and last but not least 3D acceleration support.

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