Wednesday, 3 April, 2013

Openafs 1.6.x limits

Interesting limits of openafs 1.6.x

Max Partition? max signed int64

Volume Max Size?

Bigger than 2TiB

Quota Max Size

2 TiB

Max Files per directory

64.000 entries, around 32k filenames.

Max Files per volume

Around 32 million files.

Max Filename?

255 chars

Number of ACL-Entries (per directory)?

20

Maximum number of servers for a read only volume:

13

Thursday, 21 March, 2013

Some benchmarks of RaspberryPI

I have made some quick benchmarks of my SD card on my Raspberry PI.

ionice -c 1 nice --20 hdparm -tT /dev/mmcblk0

/dev/mmcblk0:
 Timing cached reads:   280 MB in  2.00 seconds = 139.69 MB/sec
 Timing buffered disk reads:  32 MB in  3.13 seconds =  10.23 MB/sec
cat /sys/block/sda/queue/scheduler 
noop [deadline] cfq
./seeker /dev/mmcblk0
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/mmcblk0 [15193MB], wait 30 seconds
295223396
..............................
Results: 409 seeks/second, 2.443 ms random access time
for i in {1..32} ; do dd if=/dev/zero of=space.$i.4GiB.out bs=1M count=4096 ; done
4096+0 records in
4096+0 records out
4294967296 bytes (4.3 GB) copied, 802.682 s, 5.4 MB/s
^C902+0 records in
902+0 records out
945815552 bytes (946 MB) copied, 169.609 s, 5.6 MB/s
ionice -c 1 nice --20 bonnie++ -u root
Using uid:0, gid:0.
Writing a byte at a time...done
Writing intelligently...done
Rewriting...done
Reading a byte at a time...done
Reading intelligently...done
start 'em...done...done...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...done.
Create files in random order...done.
Stat files in random order...done.
Delete files in random order...done.
Version  1.96       ------Sequential Output------ --Sequential Input- --Random-
Concurrency   1     -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
raspberrypi      1G    47  98  5095   7  3618   7   349  99 12698  11 485.6  56
Latency               472ms   13531ms    8527ms   37039us   47144us   56047us
Version  1.96       ------Sequential Create------ --------Random Create--------
raspberrypi         -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  2752  63 +++++ +++  4110  60  2599  58 +++++ +++  4003  60
Latency             14651us    8503us    5143us    6866us     394us    3927us
1.96,1.96,raspberrypi,1,1363919597,1G,,47,98,5095,7,3618,7,349,99,12698,11,485.6,56,16,,,,,2752,63,+++++,+++,4110,60,2599,58,+++++,+++,4003,60,472ms,13531ms,8527ms,37039us,47144us,56047us,14651us,8503us,5143us,6866us,394us,3927us

Saturday, 16 February, 2013

Update to kibana package

I have improved the packaging of kibana for Debian. Is lintian clean and almost ready for inclusion in Debian.

kibana_0.2.0_35_g40f2512_5-1_all.deb
kibana_0.2.0_35_g40f2512_5-1.dsc
kibana_0.2.0_35_g40f2512_5.orig.tar.gz
kibana_0.2.0_35_g40f2512_5-1.debian.tar.gz

The CMS have replaced the + by _ in the filenames. Be prepared to rename back the files before doing dpkg-source -x kibana_0.2.0_35_g40f2512_5-1.dsc

Friday, 18 January, 2013

Packaged kibana into a Debian package

I have made a Debian package for kibana software. You may download the kibana_0.2.0_35_g40f2512_3-1_all.deb file or the sources kibana_0.2.0_35_g40f2512_3-1.dsc.

Monday, 12 November, 2012

Good hacks on using Debian testing

I found an interesting article on how to use Debian testing/unstable/experimental and ways to contribute back to Debian.

http://bonedaddy.net/pabs3/log/2012/10/29/thoughts-on-debian-testing/

Friday, 31 August, 2012

A Selection of talks from DebConf 2012

Sunday, 6 May, 2012

Very short review of Marune: Alastor 933

Marune: Alastor 933 Marune: Alastor 933 by Jack Vance
My rating: 4 of 5 stars

I have read this book many years ago, but I still remember the sense of wonder about the civilizations present in the story.

View all my reviews

Saturday, 7 April, 2012

"Hunger Games" vs. "Battle Royale"

*** SPOILER ALERT ***

Vi à pouco tempo o "The Hunger Games". Filme que vi com muita atenção. Tendo visto o "Battle Royale", "Battle Royale 2" e lido o livro, não fui capaz de evitar de fazer comparações entre as duas histórias.

Em relação à qualidade dos filmes, se são cinéfilos recomendo que vejam os filmes, "Battle Royale" e "The Hunger Games" e por esta ordem. Caso contrário vão ao cinema ver o "The Hunger Games".

Como não sou capaz de falar dos filmes sem entrar em detalhes da história, recomendo que vejam primeiro os filmes antes de continuar a ler este artigo.

*** SPOILER ALERT ***

Os dois filmes falam acerca de uma sociedade autoritaria, que precisa de sacrificar os jovens para manter o controlo da população. Os jovens são escolhidos à sorte para combater entre si até restar apenas um. Ao sobrevivente é destinado fama e fortuna.

O "Battle Royale" é passado num futuro próximo e alternativo. Concentra-se no drama de uma turma do secundário que é selecionada para a batalha. É bastante gráfico e realista nos incidentes e armadilhas do combate.

O "The Hunger Games" é passado num futuro distante, na 74ª ceifa anual. O combate é um reality show de TV. O filme perde tempo a explicar a motivação dos Jogos e a mostrar como estes são usados para manter a população sobre controlo. Jogando com a esperança e o medo da população, que assiste ao reality show em directo. O combate é manipulado para manter a audiência interessada e o seu medo e esperança sobre estreito controlo.

Considero o "Hunger Games" uma reinterpretação das ideias do "Battle Royale". Onde parte das diferenças deverão poder ser explicadas pelas diferenças culturais entre o Japão e o USA. Usando clixés, considero o "Hunger Games" mais POP e acessivel, o "Battle Royale" mais raw e alternativo e por isso este é um filme de culto, dentro de um pequeno grupo de apreciadores.

Não tendo ainda lido a trilogia "Hunger Games", reservo o direito a mudar de opnião.

Monday, 6 February, 2012

A Selection of Talks from FOSDEM 2012.

It was only some days ago that I made the decision to go, for the first time to the FOSDEM (Free and Open Source Software Developers' European Meeting). That was a good decision. The keynotes and the maintracks were very good, with good presentations and contents.

It is a big conference and this year, is not an exception. With 429 speakers and 430 talks at 21 rooms in only two days. It's impossible to see all the presentations. The only 5 rooms with a video camcorder to tape the talk, where: Janson, K.1.105, Ferrer, H.1301, H.1302. It's very dificult to choose what talks to see, what talks to see later in video and what talks to loose. What I leave here is my selection of talks. This selection is representative of my tastes, not of the quality of the presentations. I will give links for material that is available now. I will do periodic updates when the new material is available, the video or the slides.

   Video
   Video
   Video
   Video
   Video
   Video
   Slides
   Video
   Video
   Video
   Video
   Video
   Slides

More resources:

http://lanyrd.com/2012/fosdem/

Tuesday, 3 January, 2012

To package or not to package, that's the question.

In the past I had to install many times, by hand, extra software on Unix machines, specially because of missing useful software like a C compiler or because I like too much to use the bash. In the end it can get very messy I promised myself to never do again a make install for manually installing software in a Debian machine.

It's possible and it pays on the long run. When you take a program from outside the distribution you need to: configure, compile, install and document what you have done. So you can do it again with the next version. Specially when you have done local modifications. If you put your software inside a Debian package and follow the most sensible Debian Policy rules you get:

  • The documentation on how to configure, build and install the software is in debian/rules file.
  • It's easy to upgrade or remove the software, because is a Debian package.
  • You can use a patch system like quilt or dpatch to isolate your local changes from the upstream sources. If you create different patches files, for every logical feature you enhance or fix, it will be easier to drop them when the new version have the desired feature and to know what features needs to be ported for the new version of the upstream software.
  • You can do it even with the binaries of proprietary software. Its easy to take an rpm or tar files with the binaries and insert them inside the sources of a Debian package. With the proper care it's easy to update the sources for the next upgrade.

For example I have been doing this for packaging the pristine upstream binary of eclipse, because the teachers of my University usually requests a newer version of eclipse than what is available from Debian stable or even unstable.

Another example is the support software for HP hardware before HP officially supported Debian. I have taken the original rpm files or the scexe scripts and convert them into a debian file. Usually I need only to change two files with every new release of software, the Makefile with the name of the new rpm file and the debian/changelog with the new version and what is new.

In the end it's easier than it seams to create and maintain a Debian package. It's a steep curve, but pays off on the long run.

The good thing is all this approaches are compatible with a puppet or chef system for managing the Unix servers.

Tuesday, 29 November, 2011

Unix Backup & Recovery

UNIX Backup and Recovery by W. Curtis Preston

My rating: 5 of 5 stars

This book have given to me a completely new vision on how to deal with backups, many years ago. From my naive perspective, I have evolved to a much more complete and professional view on how to deal with backups. Being small backups of a Desktop to big backups of a modern Data Center. The lessons that I learned have been proved by time as correct.

Friday, 28 October, 2011

10 Free eBooks For Halloween With Some Links From Amazon

Here is an article with 10 Free eBooks for Halloween. For the people that like to fetch the eBooks from Amazon, here are the links. Not all of them are free from Amazon and for some titles I didn't find a cheap version that I could recomend.

Frankenstein

Dracula

STRANGE CASE OF DR JEKYLL AND MR HYDE - ORIGINAL VERSION PUBLISHED FOR KINDLE - UNIQUELY ILLUSTRATED VERSION - R.L. STEVENSON ILLUSTRATED

The Shunned House

Fall Of The House of Usher - The Complete Works of Edgar Allan Poe (Includes Essay About the History of the Horror Genre)

Tales of Terror and Mystery Illustrated

Extra: Dracula's Guest

Monday, 17 October, 2011

Free books from Amazon for Kindle? Yes.

Amazon "sells" a lot of books for Kindle and no cost. Here two links for finding them:

link1

link2

Thursday, 4 August, 2011

Preview of xorp v1.8.3 in Debian

I attended DebConf11 and my main objective was to package xorp v1.8.3 for Debian. In the spirit of release early and release often here are the links for a package compiled for Debian v6.0 aka squeeze. The work is not finished and most important was not yet reviewed by a Debian Developer. Reports of success are important.

For downloading:

xorp_1.8.3-1_wip4_bpo60_1_i386.deb

xorp_1.8.3-1_wip4_bpo60_1_amd64.deb

For accessing the sources or using apt-get add the following lines to your /etc/apt/sources.list:

deb http://debian.tagus.ist.utl.pt/debian squeeze/UNRELEASED main contrib
deb-src  http://debian.tagus.ist.utl.pt/debian squeeze/UNRELEASED main contrib

Tuesday, 19 July, 2011

De Lisboa ate Banja Luka para a DebConf11

There is online a description of the travel to Banja Luka from Zagreb, with photos and everything. So this time I will write in Portuguese for the people that prefer Portuguese to English.

A viagem de taxi até ao aeroporto correu sem problemas, não havia trânsito na ponte 25 de Abril. No check-in a fila da esquerda tinha maquinas próprias de check-in e a ajuda de uma funcionária da Lufthansa. Rápidamente fiquei com os 2 bilhetes de ida. Lisboa - Frankfurt e Frankfurt - Zagreb. Por isso despachei-me num estante. O embarque começou atrasado, estranho para uma companhia alemã. :-) A viagem correu sem problemas tirando alguma turbulência na aterragem. Em Frankfurt o céu estava cinzento e a pista molhada.

O desembarque em Frankfurt foi nas portas A do terminal 1. Nos placards o meu voo para Zagreb ainda não tinha porta de embarque, apenas Terminal B. Assim comecei a minha caminhada até às portas de embarque B, que se revelou ser bastante comprida. Demorei perto de 30 minutos a chegar à porta de embarque do meu voo seguinte. Comecei a andar, quando à minha direita vejo um imponente 747 da Lufthansa a vir em direcção à janela. Após uns minutos de espera seguiu o seu caminha pela minha esquerda. Como um elegante elefante na selva de betão de um aeroporto.

Foi uma longa caminhada através do terminal A, até encontrar o túnel de ligação para as portas de embarque B. Finalmente à chegada ao terminal B, o meu voo tinha porta atribuida, diferenta da do bilhete. O embarque começou exactamente à hora marcada. O embarque foi feito para o autocarro que nos levou até ao avião. Rápidamente estava toda gente sentada, mas a hora da partida fomos informados de um ligeiro atraso, para esperar por passageiros de outros voos de ligação.

Na chegada a Zagreb tive alguma dificuldade em perceber como era o controlo alfandegário. Filas para toda a gente ou filas diferentes para europeus e não europeus. Julgo que não queriam destinguir os diferentes tipos de passaportes. No entanto uma cabina dava prioridade a tripulações e outra para passageiros de voos de ligação.

Logo a seguir ao controlo de passporte, fica a sala com a alfandega, a maquina de ATM e á direita a recepção de bagagem. Esta maquina ATM pareceu aceitar quase todos os tipos de cartão de crédito. O meu cartão de debito Maestro funcionou, para levantar dinheiro para os autocarros.

À saída da alfandega escolhi a porta de saida da direita. Esta porta tem logo à esquerda o autocarro para a cidade, especificamente o autocarro de ligação até ao terminal de autocarros. O condutor fala Inglês, aceitou a minha bagagem e paguei o bilhete ao condutor 30kn. Julgo que este autocarro esperou um pouco mais devido ao atraso do avião. Pois partiu por volta das 20h10 em vez das 20h00. O percurso termina exactamente no terminal de autocarros, não há como enganar.

No terminal de autocarros demorei algum tempo a encontrar o sitio para vender bilhetes. Foi preciso contornar o edifício para encontrar as escadas que levam ao 1º andar onde estão as bilheteiras. As pessoas na bilheteira falam Inglês, mas precisei de mostrar o papel com o nome do destino. Pois não dizia Banja Luka com a pronuncia certa, Banhia Luka? No bilhete procurar pelo número "Peron", este indica de onde parte o autocarro, 405 no meu caso. O preço é variavel pois são varias as companhias que fazem a viagem. Pela a viagem das 22h00 paguei 108kn, o preço mais barato. Paguei extra 24kn pelas minhas duas malas. Recebi 2 papeis, estes são importantes, pois provavelmente não nos entregarão as malas se o revisor não puder confirmar o numero da mala com os dos nossos papeis.

O motorista e o revisor não falam Inglês e parecem que não fazem o esforço para perceber outras linguas, para além das linguas locais. Mas não é problema pois o autocarro faz apenas 3 paragens:

  1. fronteira, tenham o passaporte convosco e não na bagagem de porão. Preparam-se para sair do autocarro, mostrar o passaporte à policia por duas vezes e um deles policia recolher o vosso passaporte para verificações mais prolongadas. No fim o revisor irá devolver o vosso passaporte.
  1. descanso, logo a seguir à fronteira o autocarro faz uma paragem. Permite ir ao WC, fumar ou ir ao restaurante. Este não faz referencia de aceitar qualquer forma de pagamento por cartão e não comprei nada para confirmar. Cuidado para não perder o autocarro, pois não me pareceu que o revisor tenha confirmado a presença de toda a gente.
  1. Banja Luka, a chegada parece ser num simples parque estacionamento onde param os autocarros e os taxis. Fica a 3 Km de distância, por isso recomenda-se apanhar um taxi ou o autocarro. O preço médio fica em 10km ou 5 euros. O taxista não falava Inglês e não tinha troco de 50km, que a maquina do hotel me tinha acabado de dar. Acabei a receber 20 euros do troco, o que foi justo.

Penso eu porque passava da meia noite, o empregado fez um check-in rápido e ficou com o meu passporte, que foi devolvido na manhã seguinte.

Sunday, 5 June, 2011

A Not So Short Review of the Kindle 3G + Wifi

I got my Kindle 3G + Wifi (3rd generation) two days ago. In these two days I have study his capabilities.

My first impression was: "is small, light and thin." Everyone was well impressed with the quality of the screen.

I love how easy is to upload documents to the Kindle. With the 3G I can upload Amazon ebooks everywhere and when I want. They are at distance of 1 click and 15 seconds. No need for pre-upload all my ebooks to the Kindle. For my documents I can use the USB port and the Wifi connection (for free). The Amazon service for converting and upload documents means I can email the documents to my Kindle. This service is very good for doc and pdf documents. Another thing, is very nice that the services for converting Web pages offer to send by email the resulting document.

The Kindle is a good gadget for reading ebooks. The other formats like doc and pdf are very readable after conversion, if they don't depend on formating. The loudspeakers have a good sound and should be good enough for audio books

I have experimented my Kindle on the limits of is capabilities and I am well impressed. The screen is too small for reading PDF documents without conversion. But the screen have good detail (160 dpi) and you can try to read them, if you have good eyes, If not, the zoom and pan is your friend. The 600x800 resolution is too low for reading manga, japanese comics, specially because some of them have very small details.

The experimental web browser works in acceptable way with web sites with little or no graphics, like Linux Week News. The "Article Mode" makes the news sites more readable. It's a pity that the comments are not shown is this mode, at least with LWN. The experimental MP3 Player is very simple, good for background music. Not like a dedicated music player, the sound quality is good but not Hi-Fi.

There is an experimental image viewer that can show images of the most common formats, but sometimes it have problems refreshing the screen with the next image. It's good for showing pictures and if the screen was bigger it would be good enough for reading black and white comics or manga.

My surprise was with the wifi. I didn't check it's limitations and I was surprised because I couldn't connect to the eduroam network. The Kindle wifi don't work if "Wi-Fi network is an enterprise or peer-to-peer network" or "Wi-Fi network is not 802.11b, 802.11g, or 802.11n (in b or g compatibility mode)".

In this two days I found that I like my Kindle, it works as expected if you forget the WiFi issue. I really believe that is easier to read in the Kindle than a real pocket book. The problems I found in reading manga or PDFs are what other people were saying. If the web browser was a little better. This Kindle 3G is a keep, the WiFi problems makes the extra money for the 3G worthwhile for me. My other wish is an updated Kindle DX with a lower price.

Things that I would like to do next:

  • Try audio books
  • Connect the output sound to an aux entry
  • A way for converting a web site to an ebook document.
  • Using latex for generating an ebook document.
  • To make ebook documents from the intranet and other documents in heterogeneous formats.
  • Exists more readable fonts, darker, than what comes with the Kindle?
  • Try the hack for personalizing the screen savers.
  • Try the hack for configuring eduroam network on the Kindle.

Useful links for people that have a Kindle, in Portuguese:

Usefull links in English:

Reading web pages offline

Sunday, 11 July, 2010

Battle Royale

"Could you kill your best friend?" Do you want to see a shocking movie? Do you liked "Natural Borne Killers" or "Kill Bill Vol.1"?

"Battle Royale" is not a movie for the faint of heart. You see young lovers trying to kill each other. You see teenagers killed by accident. Be prepared, if you watched "Natural Borne Killers" and have not recovered yet, don't see it.

Do you want to know your answer to the first question. You want to see how people can kill for stupid reasons and in stupid situations. You mind to see blood spilt all over the place. Go see it. The story is simple but have details. The book and the movie have made a big uproar in Japan. Members of the Japanese Parliament tried to get the novel and the movie banned. But they only succeed in making then more successful.

I finished the book "Battle Royale" some months ago. I have seen in the theater "Natural Borne Killers" and "Se7en". The extreme movies that I have seen. So this movie was waiting in my list of movies "must to see".

3 out of 5 stars, Because not every one can see it.

Battle Royale imdb page

Sunday, 4 July, 2010

Nagstatmon help monitor network and servers using nagios

Monitoring a network or a group of servers using nagios have some problems. Receiving alarms by email or have a browser with a open page to the nagios site is an option that don't fit well in the work flow of some people.

Nagstatmon is a program that solves that problem. It opens a small window or icon on a taskbar of your desktop and show how many alarms are active. When an alarm triggers you can see where and what kind of alarm and easily open a connection for managing the equipment in fault.

This program is available in Debian testing (squeeze) but the package is compatible with Debian stable (v5.0, lenny).

The homepage for the software is http://nagstamon.sourceforge.net/

Monday, 28 June, 2010

Published cal-logcheck-database v 0.35

cal-logcheck-database is a personal package that I use to collect extra rules for logcheck. This rules help me keeping the logcheck reports cleaner and informative.

This version have new rules for smartmontools messages and updates the package for squeeze.

You can download the package and the source from here:

cal-logcheck-database_0.35_all.deb

cal-logcheck-database_0.35.dsc

cal-logcheck-database_0.35.tar.gz

cal-logcheck-database_0.35_i386.changes

In alternative you can install it using apt if you add the following line to your /etc/apt/sources.list:

deb     http://debian.tagus.ist.utl.pt/debian lenny/updates main

Monday, 14 June, 2010

Debian package v0.0.9-2 of switchconf hit testing

Debian package v0.0.9-2 of switchconf have migrated from unstable to testing. This new version have changed only the package, not the code of switchconf. Follows the changelog.

  * Fix bashism in a private rule on debian/rules file (Closes: #581451).
  * Add remote_fs to dependency of init.d.
  * Bump standard version to 3.8.4, no changes needed. 

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