Archive for November 2009

Ext4 Performance Improvements

Nov 24, 2009

In order to speed up the general performance of my personal computer I put an Intel X25-M SSD into it some time ago and made sure that most binaries that are needed to start up Linux are loaded from the SSD. I could not go without a conventional hard disk, though, because the storage capacity of typical SSDs (or the budget that I am willing to spend) is still too limited. While boot times already improved dramatically after adding the SSD, mounting the file systems located on my conventional hard disk was still limiting the overall speed of the boot process.

That was when I read about the performance improvements introduced by the ext4 file system.

Sparse File Support for rsync

Nov 24, 2009

From time to time one needs to migrate large amounts of data from one file system to another, such as when migrating to a new hard disk, setting up a RAID array or migrating a file system from ext3 to ext4. Each time this happens I find myself googling for the exact rsync command to do the sync operation and each time the command line parameters mentioned in most search results neglect the existence of sparse files. So, mostly as a note to myself, here is the rsync command line I tend to use when replicating data to a new file system (including sparse file support):

rsync -aqxPSH _source_ _destination_

Die Schwimmring AG

Nov 21, 2009

Mir lief gerade via jens scholz das folgende Video über den Weg. Bester Stop-Motion-Trickfilm à la Wallace & Gromit, den ich euch nicht vorenthalten möchte:

Smoking Kills... Your Warranty

Nov 21, 2009

Smoking will void your warranty. Well, not yours, but the warranty that comes with your Apple device. However, the referenced article attempts to create the impression that Apple refused to acknowledge the warranty claims because of potential health issues for its service personnel (as that is also what a couple of customers were told), but seems to mostly ignore the fact that over time cigarette smoke leaves plenty of residue [CAUTION: Explicit images, not for the faint-hearted!] on any surface it gets in touch with. I am almost certain that optical disk drives as well as heat sinks and fans would be especially affected by this. A brief Google search did not yield any results hinting at whether smoke deposits are conductive. However, if that would be the case the effect on computer hardware would be even worse.

So, why should Apple be obliged to repair a device under warranty that has been damaged by a certain practice at the user’s discretion? Nobody would request a warranty repair of a computer device that has been dropped into and consequently damaged by water…

Garmin Oregon 300 Firmware 3.30

Nov 21, 2009

In a previous post I outlined how to apply a firmware update for the Garmin Oregon series under Linux without the use of Garmin’s proprietary web updater. In the meantime, Garmin has released a new firmware revision, version 3.30, so if you’d like to update your device to that new version, just grab the .gcd file and follow the instructions in my previous post.

The Economic Impact of Facebook Games

Nov 18, 2009

If there is something that I see colleagues at work doing on a regular schedule, it is them playing games on Facebook, such as Mafia Wars or FarmVille. Games built around scam schemes as the CEO of the company behind these games openly admitted during a talk he gave.

Frankly, I could not care less about people installing spyware or adware on their machines or being tricked into subscribing to scam offers. Those people are in charge of their own destiny and chose to enroll in playing those games at their own free will. If they are falling for these scams just to advance their score in a dubious web game, well, then that’s part of the lesson they have to learn.

However, considering the immense amount of time some users are investing into gameplay there clearly seem to be some addictive aspects associated with playing Mafia Wars or FarmVille. So, what I am actually more interested in is the overall impact these games could have on our economy.

"Weiß ich nicht, ist mir aber auch egal"...

Nov 15, 2009

…solche, oder zumindest ähnliche, Antworten erhält man, wenn man den Durchschnittsbürger nach den Ursachen für die zunehmende Lethargie im Lande befragt.

Die Ironie, die dieser Posse innewohnt, ist zwar durchaus beabsichtigt, schmälert die Bedeutung des Problems aber in keiner Weise.

Was ist es denn, das Menschen das Interesse und den Spaß an der Neugier verlieren lässt?

Die neue Bedrohung

Nov 15, 2009

Mit Terrorwarnungen lockt man schon lange niemanden mehr hinter dem Kamin hervor. Da muss man schon ganz andere Geschütze auffahren. Viren zum Beispiel. Während man den klassischen Terrorist ja bekanntermaßen an seinem Äußeren einwandfrei als solchen erkennen kann, haben es kleine, unsichtbare Viren, weder tot noch lebendig, auf uns abgesehen. Ganz ohne Bombengürtel schwirren sie durch die Luft, diese unheimlichen Gesellen: Die Schweinegrippe (politisch korrekt: Neue Grippe) geht um und versetzt einen Planeten in Angst und Schrecken. “Dazu gibt es doch auch allen Grund, oder?” mag sich der geneigte Leser eingeschüchtert hinter seinem Atemschutz fragen.

Über die Verwundbarkeit komplexer Systeme

Nov 8, 2009

Ein Posting aus dem Heise-Forum zur Verwundbarkeit des LHC durch gemeine Baguette-Attacken bringt es auf den Punkt:

Re: Habe ich das richtig verstanden? Rot5 (mehr als 1000 Beiträge seit 12.12.00)

VisualBeo schrieb am 7. November 2009 18:28

Ein Vogel kann mit einem Stück Brot bei einem Zich-100-Millionen-Euro-Forschungsprojekt einen Kurzschluss versursachen, woraufhin die gesamte Anlage abgeschaltet werden muss. Wobei jeder Tag, an dem die Anlage nicht einwandfrei läuft, wiederum hundert tausende Euro kostet und die Forschung in diesem Bereich still legt.

Ich bin begeistert.

Naja, es war ja auch ein kleiner Ein-Mann-Jäger, der den Todesstern zerstört hat!

Using Valgrind to Profile KDE Plasmoids

Nov 1, 2009

During the past days I prepared my KDE Weather Ion for for inclusion in the KDE Trunk. Before entering the review phase, the KDE people are asking for a memory leak analysis of the new code using Valgrind. That’s easier said than done as I could not really find some documentation on how to run a Plasmoid (along with its data sources) through Valgrind…

After a little bit of googling I finally figured out how to do this and would like to use this post to document my findings.

Well, the key to the solution lies in a neat tool called plasmoidviewer, which can be used to run a Plasmoid as a standalone application. From that point on, things get easy: Just run Valgrind on plasmoidviewer along with the desired Plasmoid and you are done, such as in (this example will run the leak check on the Weather Plasmoid):

valgrind --tool=memcheck --leak-check=full plasmoidviewer weather