Tue, 20 Aug 2013
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.Thu, 21 Mar 2013
Noticed with a lot of happiness today that Gnome extensions list a new one showing weather information. (:Fri, 08 Mar 2013 Sun, 21 Oct 2012
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.Sat, 20 Oct 2012
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?!Fri, 05 Oct 2012 Mon, 11 Jun 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. (;Thu, 31 May 2012
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. (:Sun, 06 May 2012
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.Mon, 02 Jan 2012
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.Thu, 20 Oct 2011
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.Tue, 20 Sep 2011
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.Tue, 23 Aug 2011
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.Wed, 27 Jul 2011
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.
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
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.Wed, 02 Mar 2011
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.Wed, 26 Jan 2011
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.Mon, 13 Dec 2010
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:
The symmetric command for stopping is cupsdisable.Tue, 02 Nov 2010
At the mini-DebConf Paris 2010 the Debian linux-2.6 team released latest 2.6.32-27 adding stable 126.96.36.199 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.
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
I am very sad to have missed the opportunity to meet you in person. You are missed. Rest in peace, my friend.Sat, 28 Aug 2010
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.Thu, 26 Aug 2010
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.
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.Wed, 21 Jul 2010
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.Thu, 22 Apr 2010
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.
P.S.: Ubuntu Lucid pushes out klibc 1.5.17 thanks to Colin Watson.Tue, 06 Apr 2010
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.
Newer initramfs comes with lots of fixes and new features:
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.
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
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. :)Wed, 03 Mar 2010
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 188.8.131.52 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.Thu, 03 Dec 2009
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.
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."
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.Tue, 27 Oct 2009
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:
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.Wed, 21 Oct 2009
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 email@example.com.Tue, 20 Oct 2009
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. :-)Tue, 24 Mar 2009
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.Mon, 09 Mar 2009
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.Thu, 05 Feb 2009
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:
As bonus to some cleanup and docs update we have also seen a Ubuntu sync and are not too diverged.Fri, 19 Sep 2008
playlist sept. 2008
double *bounce* triple *bounce*
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.Wed, 25 Jun 2008
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.