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the avatar of Matthias Hopf

RAnsrID: Galois Field / Reed-Solomon code rewrite pending

While starting to implement error resilience (not erasure resilience, which is already working nicely) in my RAID-lookalike multi-disk block device RAnsrID, I finally had to notice that I didn't understand one aspect of Galois Field mathematics - the Reed-Solomon representation type has heavy influence on how to deal with errors (read: corrupted data).

So far, I only understood the canonical matrix style representation (basically a linear combination over the data disks for each redundancy disk). Turns out that with polynomial representation you can create way better (read: faster) algorithms for error correction - according to my analysis, erasure and error recovery is O(N²), compared to O(N³) for erasure correction in the linear combination case, and unknown (presumably O(N³⋅M²)) in the error case (N: total number of disks, M: number of redundancy disks).

Thus I will rewrite the redundancy routines based on Phil Karn's Reed-Solomon implementation - the best implementation with an open license I could find. Most implementations (like in par2) don't bother with error correction, and use block-level checksums to detect errors. That done, erasure recovery can be used. Needless to say, this is no option for my block device (where and why should I store the checksums).

No need to say that this delays delivery timeframe of RAnsrID further; especially as I'd like to incorporate the change in an at least data preserving backwards compatible way.

Also Hackweek 6 wasn't as productive as I hoped; I only managed to get the test suite up and running. Oh well.
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World IPv6 Day - Dia Mundial IPv6

WORLD IPV6 DAY is 8 June 2011 – The Future is  Forever

Sobre o World IPv6 Day - Dia Mundial IPv6

No dia 08 de junho de 2011, Google, Facebook, Yahoo!, Akamai e Lamelight Networks, assim como as empresas brasileiras Terra, Campus Party, IG, Dualtec e Nomer, são algumas das principais organizações que irão oferecer os seus conteúdos também em IPv6 para um "test flight" de 24 horas. O objetivo desse dia de testes é motivar as organizações de todos os setores - fornecedores de serviços de Internet, fabricantes de hardware, fornecedores de sistemas operacionais e empresas de Internet - a preparar os seus serviços para o IPv6 e assegurar uma transição bem sucedida, com o fim dos endereços IPv4 livres.

Junte-se a nós neste grande teste mundial e ajude a acelerar a dinâmica da implantação do IPv6.

O IPv6 World Day acontecerá simultaneamente em todo o mundo. No Brasil (horário de Brasília), o período de 24h de testes começará no dia 07/06/2011 as 21h, e irá até dia 08/06/2011 as 21h.

Como Fazer Parte

Interessado em juntar-se às outras organizações que estão participando desta iniciativa?

Acesse o link http://isoc.org/wp/worldipv6day/how-to-join/ e encontrará todas as informações para participar do World IPv6 Day.

Acompanhe

No twitter - #diadoipv6 - #worldipv6day - #ipv6br

A equipe do IPv6.br disponibilizou um chat para tirar dúvidas e trocar experiências. Acesse via web:

http://www.ipv6.br/bin/cgiirc/irc.cgi

Ou utilize o canal #ipv6.br da rede Freenode no IRC.

Testes IPv6

Quer saber se seu computador já opera com IPv6? Utilize este teste: http://test-ipv6.com.br.

Quer saber se um sítio Web qualquer já está disponível via IPv6? Utilize este teste: http://validador.ipv6.br.

Momento da Transição

Com o esgotamento do IPv4 no estoque central, é cada vez mais urgente a implantação do IPv6 na Internet, em especial nos sites e outros serviços Web. Saiba mais assistindo o vídeo abaixo:

Mais informações sobre o World IPv6 Day no sítio: http://isoc.org/wp/worldipv6day/.

Mais informações sobre o IPv6 em: http://ipv6.br.



Fonte: http://www.isoc.org.br/index.php/worldipv6day






Veja isso: As várias correntes de pensamento e de ações, para se ter uma Internet Banda Larga Melhor e Livre no Brasil







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the avatar of Efstathios Agrapidis

Greek openSUSE community, Translation of openSUSE Weekly news in Greek(issue 177)

Hello out there,

I am very pleased to announce the new issue (177) of openSUSE Weekly
News in Greek. In this one you will read about:

* openSUSE renames OBS
* Bryen Yunashko: Ready…Set…Code!
* Andreas Jaeger: Factory Progress
* Matt Barringer: SUSE Gallery Desktop Client
* Christos Bountalis: A utility for merging configuration / sysconfig files – Week 1
Report

And of course many many interesting news about openSUSE, plus usefull
advice for making our lives easier.

Enough… read more at: own.opensuse.gr or at
http://el.opensuse.org/Weekly_news.

Looking forward to hearing your comments, advice and anything you would
like to read about at the next issue.

The openSUSE Weekly News is translated in the Greek language from issue #150. You can read older translated issues here: http://el.opensuse.org/Κατηγορία:Weekly_news_issues

Enjoy it!
Efstathios Agrapidis (efagra)

the avatar of Efstathios Agrapidis

Greek openSUSE community, Translation of openSUSE Weekly news in Greek(issue 176)

Hello out there,

I am very pleased to announce the new issue (176) of openSUSE Weekly
News in Greek. In this one you will read a lot about free (as in freedom) software conferences, either they have already been done, or they will be done in the direct future.
A little sample from the subjects:

* openSUSE Conference 2011 to be creative and open!
* Manu Gupta: My GSoC Project – SaX3
* Michal Hrušecký: LinuxTag 2011
* Will Stephenson: Have you BURPed yet today?
* Anastasios Ksouzafeiris: How to install Enlightenment (E17) in openSUSE 11.4

And of course many many interesting news about openSUSE, plus usefull
advice for making our lives easier.

Enough… read more at: own.opensuse.gr or at
http://el.opensuse.org/Weekly_news.

Looking forward to hearing your comments, advice and anything you would
like to read about at the next issue.

Enjoy it!
Efstathios Agrapidis (efagra)

the avatar of Andreas Jaeger

Factory Progress

A lot of things are happening in our Factory distribution that will be released in November 2011 as openSUSE 12.1 and I’d like to point out a few things from the last few weeks that users and developers of factory shouldn’t miss.

Roadmap openSUSE 12.1

Stephan “Coolo” Kulow has updated the openSUSE 12.1 Roadmap, the next milestone is Milestone 1 which is delayed and targeted now for release on Tuesday, 30th May. The next paragraphs highlight some of the updates for this versions.

GCC 4.6

The GNU Compiler Collection has been updated to version 4.6, the list of  changes includes the following new warning that will be visible while compiling packages for openSUSE Factory:

  • “New -Wunused-but-set-variable and -Wunused-but-set-parameter warnings were added for C, C++, Objective-C and Objective-C++. These warnings diagnose variables respective parameters which are only set in the code and never otherwise used. Usually such variables are useless and often even the value assigned to them is computed needlessly, sometimes expensively. The -Wunused-but-set-variable warning is enabled by default by -Wall flag and -Wunused-but-set-parameter by -Wall -Wextra flags.”

Some packages have been failing by the new GCC due to new warnings and new optimizations and most have been fixed already but please double check that your packages are building and running fine.

RPM 4.9

Michael Schröder announced RPM 4.9 for Factory. He explains the main packager visible changes as:

“Besides some bug fixes and an update to a newer BerkeleyDB
library rpm-4.9.0 contains plugin architecture for dependency
generation. In older rpms, the internal dependency generator
was pretty much hardcoded in C, so we always used the old
external one to generate dependencies. With rpm-4.9.0, the
internal generator has become flexible enough so that we
can use it.

This means for you, that rpm will no longer use the %__find_provides and %__find_requires macros. Some packages redefined those macros to be able to filter the generated dependencies.
This will no longer work in rpm-4.9.0. Instead, support for
dependency filtering was added to rpm…”

GNOME 3

GNOME 3 has now hit Factory as well and Vincent Untz explained how to fix failures due to the large push.

Linux Kernel 2.6.39

This update was a “boring” update – nothing broke AFAIK ;), so I hope it’s a solid version. Users will benefit from the new features in it. 2.6.39 is the first kernel without the Big Kernel Lock at all!

Packaging Changes

Besides new software, also new ways of handling it get introduced. The following catched my eyes:

Rpmlint update

Ludwig Nussel updated rpmlint to version 1.2 and explained the new warnings about packaging of rpm packages – and what to do about them.

Changing the process of Factory submissions with the Open Build Service

Now with every submission to Factory scripts are run automatically that do two different reviews before the package goes to human check-in review:

  • The “legal-auto” review checks the updated package for changes in licenses.
  • The “factory-auto” review checks that the updated package builds actually in the devel project – and if not, rejects it.

The “legal-auto” review has quite a long backlog at the moment and Jürgen is working on moving some of the checks to rpmlint or osc checks – so that the packager notices and fixes them before submission to Factory.

Also, you can now submit packages to Factory even if you are not the maintainer of the package but in this case the maintainer (packager) gets a review request to review that the package really can go to factory and thus a plea to packagers to handle their review requests.

openSUSE Conference

The openSUSE Conference is this year co-located with the SUSE Labs conference. Join us to present and discuss also Factory related topics. The Call for papers is open now!

I’m interested on feedback on this article – should I start a series?

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A utility for merging configuration / sysconfig files – Week 1 Report

It’s less than a week, that GSoC 2011 coding period have begun. This is my first report for the project.Every Friday I will make a report in this blog to share with you the progress I am making on the project.So what did I do during these first days?

First of all I created an online repo on GitHub and I forked the Augeas project. That will permit me to use version control of my project “GIT” during the implementation and retain an online repo where I can commit my changes to, while experimenting with the source code. This gave me the opportunity to practice more with git, create branches merge commit changes etc. I have to admit that until now, I didn’t used a version control system much, but i really don’t know why?!?! Really git is awesome and can save the developer valuable and useful time.

Next, I continued with trying out OBS for the first time, the openSUSE Build Service, that just renamed to Open Build Service. Even thought i faced some troubles in the start finding my way around (packaging was a new thing for me, and after using obs I have to say that it is not as hard as I initially believed), with the help of my mentor I think I can understand now better the service and use it. But why use OBS to package so early in the project? Well we thought that by using obs we will be able to create packages (please care they are experimental ) with the changes i make, so other people can try them out if they are interested and maybe help with future debugging.

Finally among my initial experiments with Augeas source code, I have created a branch “helloworld” on my git repo, whether i added a simple hw – Hello world command in the augtool that is contained within Augeas. That command prints as you may have guessed :), a hello world message on screen. Then i compiled the project by using the sources of the specific branch, and at the end i used obs to create some packages that can be found on my obs repo :D.

As I had not any important experience with building software and packages, I occupied myself this week mainly with administration actions. Which however, will help the community and of course everyone interested in my gsoc project, to follow the changes, make suggestions, and contribute with new ideas, but will also help in the latter phase of integrating

Conclusion

The progress of the week 1 in bullets:

  • created git repo online through GitHub
  • practice with git
  • compiling packages from git sources
  • Learn the basics about using OBS
  • experimenting with augeas code, and creating a small command as a test
  • creating openSUSE packages through OBS

The GSoC have just begun, and I have already learned many new and very exciting things. This summer will be very interesting for sure!!! Now i will focus on the actual coding and specifically in the merging procedure that will used in Augeas. Till the next report,

Best Regards,
Christos Bountalis

[1] http://download.opensuse.org/repositories/home:/mpounta/openSUSE_11.4/
Notice: This is the first time I compile and package a project with obs, therefore the packages inside the repo are highly experimental and only for testing purposes.

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As várias correntes de pensamento e de ações, para se ter uma Internet Banda Larga Melhor e Livre no Brasil

Os mais conhecidos:



Primeiro:


Plano Nacional de Banda Larga (PNBL)

O Plano Nacional de Banda Larga (PNBL) visa oferecer uma definição de banda larga que não se baseie em um valor numérico, mas que reflita a constante necessidade da infraestrutura de telecomunicações ser capaz de suprir a cesta de serviços e aplicações que dela se utilizam, de forma a tornar possível à sociedade ter acesso a internet do futuro. A meta para que as operadoras participem é oferecer conexão à internet na velocidade de 1 Mbps por R$35 mensais nos estados onde não houve redução de ICMS para o serviço. Onde houve a redução custará R$28,90. Em compensação, as telecoms serão autorizadas a entrarem no mercado de tv por assinatura.


Fonte: http://pt.wikipedia.org/wiki/Plano_Nacional_de_Banda_Larga




Segundo:


Democratização da internet

Banda largaA UENF é uma das instituições do país a participar das campanhas "Banda larga é um direito seu" e "Democratização das comunicações".
Para saber mais, leia os textos abaixo:
Crítica ao novo rumo dado às políticas publicas de banda larga
Relatório da Proteste sobre irregularidades nas concessões de Telecom
Nova_imagem.JPGTexto base que saiu das plenárias do Rio de Janeiro sobre a democratização das comunicações
Veja ainda o vídeo sobre o debate na Câmara dos Deputados acerca do novo marco regulatório das telecomunicações
Email para adesão à campanha "Banda larga é um direito seu": campanhabandalarga@gmail.com
Email para adesão à campanha "Democratização das comunicações": frentecom@gmail.com

Fonte: http://www.uenf.br/




Terceiro:

Para que o Brasil tenha uma Internet Banda Larga melhor:

FCC: menos de 4 mbps não é banda larga (nos EUA)








Quarto:













Redes: PTTMetro Brasil, RNP, RedeRio, UFRJ, UERJ, IFRJ, IFF, UFF, UENF, entre outros.











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the avatar of Thomas Thym
the avatar of Frédéric Crozat

GNOME 3 Live image release 1.3.0 - VirtualBox, here we come

Hi all,

Génie de la Bastille

good news for Virtual Machine addicts : VirtualBox team has fixed issues which were preventing VirtualBox to work properly with GNOME Shell. You need VirtualBox release 4.0.8 (minimum) and GNOME 3 live image release 1.3.0 (it contains updated VirtualBox guest additions, required for openGL).

To download the image :  http://www.gnome.org/getting-gnome/

Enjoy.

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Εξόρμηση ΕΛ/ΛΑΚ

Το ξυπνητήρι χτύπησε 5:45 και σηκώθηκα αμέσως από φόβο μην με πάρει ο ύπνος πάνω στο χουζούρεμα, έφτιαξα καφέ στον φούρνο μικροκυμάτων,έκανα ένα γρήγορο ντουζάκι και ετοίμασα την τσάντα μου. Απάντησα κάποια από τα μέηλ μου και  η ώρα ως δια μαγείας είχε πάει 7:15, πήρα ένα ταξί και πήγα στον σταθμό τον τρένων. Προορισμός: Λάρισα

 Ένα από τα πράγματα που λατρεύω είναι οι μικρές εξορμήσεις, όταν αυτό συνδυάζετε και με κάτι ενδιαφέρον όπως ένα συνέδριο για το ΕΛ/ΛΑΚ με πολλές και ενδιαφέρουσες ομιλίες, τότε μιλάμε για μια πολύ καλή φάση.
 Πολλοί ίσως αναρωτηθείτε για ποιον λόγο δεν έκατσα Θεσσαλονίκη να δω το κομμάτι του συνεδρίου εκεί και αποφάσισα να μπω στην διαδικασία να πάω στην Λάρισα, σας είπα ότι λατρεύω τις εξορμήσεις; Επίσης αποφάσισα να εκμεταλλευτώ στο έπακρο τις 2 μέρες ρεπό που είχα όσο ακόμη το καλοκαίρι δεν είναι στα φόρτε του. Σημαντικός παράγοντας και ότι ήθελα να δω τους φίλους μου εκεί καθώς και να μπω για ακόμα μια φορά στο φανταστικό κλίμα που επικρατεί στο δωματιάκι του Linux Team.

 Παρόλο που είχα αποφασίσει να είμαι τουρίστας αυτή την φορά και να μην μπλεχτώ με booth και τέτοια τελικά με 'έχωσε' ο Diamond_gr στο Gnome3, νιαρφ. Δεν πειράζει, την επόμενη φορά...

 Το τρένο φτάνει σε λίγο και παρόλο τον καφέ που ήπια ακόμα νυστάζω, πράγμα που υπερνικά την θέληση μου να μπλογκάρω, οπότε...