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Saturday 30 August 2014

A Selection of Talks from DebConf14.

This year I came to DebConf14. It's the anual conference of Debian. It's an interesting conference where the people get together to talk and hack about Debian. This year have the big bonus of a Q&A from Linus Torvalds.

Here is a selection of talks from DebConf14.

  Video
  Video
  Video
  Video
  Video
  Video
  Video

Sunday 24 August 2014

Published switchconf v 0.0.14

I have published a new version of switchconf, v0.0.9.

Can be downloaded from switchconf_0.0.14.orig.tar.xz

This is the relevant part from the Changelog.

 * Force the use of bash, instead of a POSIX shell.

Friday 21 March 2014

Align LVM PV with SSD erase blocks

I found this article from Theodore Ts'o, interesting.

Sunday 2 March 2014

Published switchconf v 0.0.13

I have published a new version of switchconf.

There are a number of changes since the previous public release 0.0.9 that I have to thank to John Halam. He sent me a big patch with a lots of new features that I am integrating one by one.

You may download switchconf from here.

Saturday 1 February 2014

Collect and keeps up to date the system information using sysinfoupdate

In 2005 I was looking for ways to auto collect information about a Linux server. The information was to be used in case of bare bones recovery. I didn't found a satisfactory program so I created one, sysinfoupdate. This program have been growing long this years and now is a system that helps to maintain a diary of a Linux Installation. The diary records all the important changes the sysadmin does to the system. This records can be used during recovery after a broken hardware or to detect what change may be causing a malfunction, for example.

It's use is very simple, create a diario directory in your home directory, for example /root/diario, and then run sysinfoupdate. Inside diario you will find a group files with textual information about your system. It works best if you run it as superuser and you keep track of the changes under a version control system, like subversion or git.

You can download the Debian package here or download the source from here.

A Selection of Talks from FOSDEM 2014.

It's that time of the year where I go to FOSDEM (Free and Open Source Software Developers' European Meeting). The keynotes and the maintracks are very good, with good presentations and contents.

It is a big conference and this year, is not an exception. With 445 speakers and 512 talks at 22 rooms in only two days. It's impossible to see all the presentations. This year all the rooms have a video camcorder.

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: video or slides.

  video
   Video
   Video
   Video
   Video
   Video
   Video
       Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video
   Video

Monday 15 July 2013

Update to kibana package II

I have improved the packaging of kibana for Debian.

  • Add missing dependency on ruby-fastercsv.
  • Fix init.d status.

kibana_0.2.0_35_g40f2512_6-2_all.deb
kibana_0.2.0_35_g40f2512_6-2.dsc
kibana_0.2.0_35_g40f2512_6.orig.tar.gz
kibana_0.2.0_35_g40f2512_6-2.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_6-2.dsc

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

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