Category Archives: Technology

Is your Chrome bigger than mine? How Chrome ate 21GB of storage

I’ve been playing with the macOS Sierra Golden Master for a few days and ran into the new storage optimization app that is now included in macOS. It prompted me that I was running low on disk space, and displayed the following dialog. The first item on the list was a bit shocking:

chrome-21gb

How could Chrome be using 21GB of my precious SSD space?!

Continue reading

The Too Good To Be True Filter

I just published a new post on the Datacratic blog: The Too Good To Be True Filter.

At Datacratic, one of the product we offer our customers is our real-time bidding (RTB) optimisation that can plug directly into any RTBKit installation. We’re always hard at work to improve our optimisation capabilities so clients can identify valuable impressions for their advertisers. Every bid request is priced independently and real-time feedback is given to the machine learning models. They adjust immediately to changing conditions and learn about data they had not been exposed to during their initial training. This blog post covers a strange click pattern we started noticing as we were exploring optimized campaign data, and a simple way we can use to protect our clients from it. Read more…

Make OSX’s top behave like Linux’s top

OSX’s top program doesn’t quite behave like its Linux counterpart out of the box. For me, the two biggest problems are that processes aren’t sorted by CPU usage and the top program itself uses 10% of the CPU because it calculates all sorts of statistics about memory and shared library usage that I personally don’t care about.

There are a series of flags that you can pass to OSX’s top to have its behavior be closer to Linux’s top. I have created the following alias to that effect :

alias mytop='top -s1 -o cpu -R -F'

The display is updated every second, processes sorted by CPU usage and no unnecessary statistics are calculated. Instead of 10%, top uses only 2% of the CPU.

pfSense : a software alternative to your old router/firewall

My old D-Link router, like pretty much every other router I’ve ever owned, wasn’t very reliable in some way and so I was looking for open-source alternative firmwares like Tomato to flash it with. With the clear lack of effort put into the official firmwares, I thought it couldn’t hurt to try. Unfortunately, my router wasn’t supported by any third party firmware.

During my search, I however stumbled upon pfSense, a Free-BSD based router/firewall distro. It’s small (<100mb), runs on a 100MHz PC and includes all the features you would get on a very expensive commercial router (Firewall, NAT, VPN server, usage graphs, dynamic DNS support, per-ip bandwidth usage, QoS, etc).

Throughput on WAN interface

I already had a dedicated fileserver so I installed pfSense as a VM on it using VMWare (I could also have done it with VirtualBox, a free alternative to VMWare). All you need are two NICs. I now only use my old router as a wireless access point because pfSense naturally has a DHCP server. I could even completely let go of my D-Link router if I added a wireless NIC in my server.

If you have an old PC lying around or one that could be a host to a pfSense VM, all you might need is an extra NIC to get an enterprise-grade router that will cooperate a lot more than any cheap 50$ D-Link/Linksys/Netgear/etc router.

Achat de musique en ligne? Finalement oui!

Je refusais systématiquement de considérer l’achat de musique en ligne pour deux simples raisons :

  1. Protections DRM (détails sur Wikipedia)
  2. Mauvaise qualité d’encodage

Avant hier, j’ai découvert une artiste dont la musique semblait intéressante. Comme j’essaye toujours d’encourager les artistes inconnus qui tentent de percer et que c’était en plus une Québécoise, j’ai décidé d’acheter son CD. Mais pourquoi devoir encombrer mon étagère d’une autre pochette que je ne retoucherai plus jamais après avoir copié le CD sur mon laptop ??

Ce n’est pas le scoop de l’heure, le service étant disponible depuis 2007, iTunes offre une partie de son catalogue en format Plus, ce qui signifie des fichiers libres de DRM et encodés en AAC 256kbps, un niveau de qualité largement suffisant.

En deux clics et 9.99$ plus tard (au lieu de 13.99$+taxes en magasin), je téléchargeais le CD à 1MB par seconde. Moins d’une minute plus tard, j’étais donc en train de profiter de ma nouvelle musique en ayant sauvé de l’argent et en ayant diminué mon empreinte écologique par rapport à l’achat d’un vrai disque.

Un achat concluant. Ce sera probablement comme cela que j’achèterai toute ma musique à l’avenir, tant que les maisons de disque consentent à vendre leur musique libre de DRM. Vérifions quelques artistes québécois sur iTunes :

  • Dumas : aucun album en format Plus.
  • Les Cowboys Fringants : seul l’Expédition est en format Plus.
  • Pierre Lapointe : aucun album en format Plus.
  • Ariane Moffatt : aucun album en format Plus.

LaTeX en WordPress

En cherchant un peu sur le net pour trouver comment insérer du LaTeX dans une entré de blog, je suis tombé sur le site Using LaTeX in WordPress qui fournit toutes les informations nécessaires pour le faire.

Certains sites offrent même un service web qui permet d’insérer une image avec une adresse contenant l’équation LaTeX désirée dans son document et leur serveur la générera automatiquement sur demande.

Par exemple, cette adresse :

<img src="http://www.codecogs.com/eq.latex?\tiny \int_{-\infty }^{\infty }e^{-x^{2}}\;dx=\sqrt{\pi }" />

donnera  : .

Google Trends

Je suis tombé sur un outil très intéressant de Google Labs hier : Google Trends.

With Google Trends, you can compare the world’s interest in your favorite topics. Enter up to five topics and see how often they’ve been searched on Google over time. Google Trends also shows how frequently your topics have appeared in Google News stories, and in which geographic regions people have searched for them most.

Quelques graphiques intéressants :

Des heures de plaisir en tout cas.

Interesting addition to unicode

A good friend of mine, and fellow trekkie, showed me something very interesting in the unicode man page. (Type man unicode on a unix system, or you can get it here)

UCS  contains the characters required to represent practically all known languages. This includes not only the Latin, Greek, Cyrillic, Hebrew, Arabic, Armenian, and Georgian scripts, but also also Chinese, Japanese and Korean Han ideographs as well as scripts  such  as Hiragana, Katakana, Hangul, Devanagari, Bengali, Gurmukhi, Gujarati, Oriya, Tamil, Telugu, Kannada, Malayalam, Thai, Lao, Khmer, Bopomofo, Tibetan, Runic, Ethiopic, Canadian Syllabics, Cherokee, Mongolian, Ogham, Myanmar, Sinhala, Thaana, Yi, and others. For scripts not yet covered,  research on how to best encode them for computer usage is still going on and they will be added eventually. This might eventually include not only Hieroglyphs and various historic Indo-European languages, but even some  selected artistic scripts such as Tengwar, Cirth, and Klingon. UCS also covers a large number of graphical, typographical, mathematical and scientific symbols, including those provided by TeX, Postscript, APL, MS-DOS, MS-Windows, Macintosh, OCR fonts, as well as many word processing and publishing systems, and more are being added.

When Klignon get’s added to unicode, we should all take a Romulan Ale (or maybe more to the point, a barrel of bloodwine) to celebrate!

Qapla’!