Martín A. Márquez - Home

Article published at Zauber Blog

2009-02-24T17:10:00Z

As I didn't write much on this blog I wanted to post a link to an article that I published in the Technical Blog at Zauber

The idea of the article is to discuss design principles of Object Oriented Programming trying to show that many times we use to design poorly what are supposed to be Object Oriented applications. I used Java as an example, the restrictions that the language impose and also some thoughts of how a good design should be.

Here is a link to the article.

Popego in TechCrunch50

2008-09-09T16:20:00Z

Popego was selected as one of the 52 finalist companies for TechCrunch50. Today the presentation took place. Santi Siri and Emiliano Kargieman just finished doing a great presentation about Popego, we are all very happy of user feedback and the community response to the presentation, the beta is finally launched and you can get your account at http://popego.com/signup. Here is a review of the site: http://www.techcrunch.com/2008/09/09/popego-tailors-the-social-graph-to-your-interests/

Better images for Argentina in Google Maps

2008-08-04T12:18:00Z

Finally, Las Leñas can be seen in Google Maps with a good detail. It seems that Google finally put better satellite photos of Las Leñas. Here is a flof embedded map to see them: <iframe src="http://flof.com.ar/bin/map/embed/?ll=-70.08281707763672,-35.14750331465392&zoom=0&&filterEnabled=false&width=480&height=320" frameborder="0" height="320" width="480"></iframe>

LG Viewty (Or Beauty?)

2008-07-17T21:56:00Z

Yesterday I went to the presentation of the new LG phone by LG and Movistar. The first thing that you think of it is that you don't know exactly which part of this new gadget is more important, the camera or the phone itself? (I think that LG also played with the name because of the great design this apparel holds). Here is a video to understand what am I talking about:

LG demonstrates once more that they are able to compete in the Hi-end of mobile, the technology present in Viewty is incredible and the usability of it produces a great user experience to those who can have the privilege to own the phone. Furthermore, LG surprises us, again, with a great yet simple design, as in the LG Champagne or Scarlet. here are some of the characteristics of Viewty:

Camera / Video
- 5 Mega Pixel camera certified by Schneider-Kreuznach for clear shots
- Manual Focus & Auto Focus
- Xenon light for shot in low light
- Mobile XD Engine
- 30fps VGA, 262K TFT LCD for clearer and sharper pictures and videos
- Video can be filmed endlessly according to memory capacity
- Ultra High speed video capture (120fps)
- Divx Playback (up to VGA 30fps)
- H.264, H.263, MPEG4
- TV out
Connectivity
- HSDPA 3.6Mbps, EDGE
- WAP 2.0
- Bluetooth 1.2 (AD2P,BPP)
- USB 2.0 High Speed/ Bluetooth 1.2
- PictBridge(Printer direct connect via USB cable) &BPP (via Bluetooth)
Design
- Dimensions: 103.5 x 54.4 x 14.8 mm
- 3.0” Wide LCD touch-screen, 240 x 400 pixel (WQVGA)
Music
- MP3 Player
- Multi Codec support : MP3, AAC/AAC+/AAC+Enhanced, Midi, XMF, SMAF
Others
- Battery: 1,000 mAh
- Memory: on-board Memory (100Mb), External Memory (MicroSD, up to 4GB)
- Weight: 112g
- Standby time, Max (hrs): 434hrs(GSM) , 454hrs(3G)
- Talk time (hrs): 355min(GSM), 233min(3G), 138min(VT)
- Direct uploading to YouTube.com, Google friendly, Handwriting Recognition/Handwriting Editing, DivX mobile profile, TV out, Document viewer

To have a better understanding I uploaded some photos: <object type="text/html" height="300" width="400" data="http://www.flickr.com/slideShow/index.gne?user_id=23148115@N05&tags=viewty">

I've really found this phone amazing, It´s simple, nice and very functional. It´s sold by Movistar at $1299, not a high price for the uses it has.

Iphone 3G launched

2008-07-11T15:32:00Z

Today started selling 3G Iphones in the states and some other countries. In Argentina Claro seems to be the one that will start selling this phones; Movistar and Personal while they asured that will sell this incredible gadget they didn't confirm the date.

Apple strategy seems great, they will flood the market with a content selling device (games, songs, videos, etc) and every transaction of this content will pass through their store surely generating a gigantic revenue. I don't know if the cellular companies understand that apple in some way is getting some part of their market share in the content market.

New Iphone 3G

2008-06-10T10:09:00Z

Apple announced its new Iphone with 3G technology.

It was no secret that a new phone from apple was going to be announced, but nevertheless, Mr. Jobs keynote make a lot of Apple fans happy feeling eager to buy this new gadget.

I couldn´t see many big changes but the 3G technology, the GPS, the new 2.0 OS (that will also be available as an Iphone 1 upgrade) and the very low price, starting at $199, may prove sufficient, in my opinion, to win the multimedia phones war.

The design seems very similar but I think extra convinient buttons are being added to the device. Furthermore, the dimensions of the Iphone 3G are pretty the same, only a little bigger but 2 grams lighter.

One of the biggest problems that is being discussed in some forums is the legal part of the operator contracts. It seems to be good sources of information that indicates that the only way to get an Iphone 3G will be having a contract with the operator (this seems to be a big difference with Iphone 1 selling model), so it will be maybe imposible to get an Iphone without the 1 or 2 anual contract engagement. In Argentina the only one that talked about an agreement with Apple is Claro.

Some links:

About Web 2.0 & 3.0

2008-05-22T20:40:00Z

Since the Web 2.0 term was created many different significances were given to it. It's obvious that Web 2.0 implicates a lot of different things but all of them are only consequences of, in my opinion, its key feature. In the same way I think Web 3.0 has a central concept around which much more other characteristics will arise.

Web 2.0

I think Web 2.0 central concept is user generated content (or user interaction with the web). In early internet time, most of the content was generated by each site and users mainly surfed the web con consume this content. Since the appearance of forums, blogs, wikis, social networks, etc internet users started not only to consume content but also to generate content and this was one big change in the web.

Almost every other aspect of Web 2.0 (Or technologies associated with Web 2.0), I believe, is a result of this centralization of the user in the web. These are some examples:

RIAs: As the user became more active in the web, the need of better User Interfaces were needed, giving the user easier ways to contribute and participate in these sites.
Ajax: In order to develop these RIAs, this technique, known some time before the term was invented and got a lot of hype since then.
Folksonomy (a.k.a. Collaborative Tagging): As many users needed to classify the contents in the web, typical taxonomy was not applicable. The problem was that a much more flexible (and fuzzy?) way had to be used, so this way to organize the stuff proved to be better.
Syndication: As the content started to be generated by the users, it started to grow much more faster than anytime before, that's when Web Syndication, became popular in order to have a really great way to stay updated without having to visit every site you may be interested in periodically.
APIs: When the users started to put content in the sites, they realized that was difficult to get in or out this information, so the APIs came to the rescue as a way to interconnect different Web 2.0 applications.

Many more can be found, and discussed, but these ones seems to be the most clear examples of the importance of User Generated Content around Web 2.0.

Web 3.0

Here the main content is the web becoming Semantic. The idea is to start giving significance to the content and information that is in the Web. Once again, many applications, technologies and developments are going to take part (some of them already started) but I think this one is going to be much more impressive in the technological view of the change while the Web 2.0 was an incredible change for the user point of view. The one of us that are very related to the development of the web can be sure to expect great changes and new ways to use the web. This will create a whole different playground to creative minds that may take advantage of the Semantic part of the web and I have no doubt that the end will be astonishing applications that maybe we can't imagine now.

Smalltalk and XUL

2008-05-19T11:53:00Z

Smalltalk is one of the languages that's getting some hype during the last time and XUL is Mozilla technology to do RIAs much more easier than using HTML and javascript. A post that appeared en Weekly Squeak shows how to combine these two technologies in order to do great applications using them.

This post shows and give some examples of how to develop a Rich Internet Application using the best object oriented language and an excellent new way t o do fantastic front ends in the web.

The idea is to use Seaside with specific XUL components to develop the stuff. The model es pretty much alike the one you use when developing with seaside but is much more easier to do richer User Interfaces with less effort. You can download a Squeak image with all the code and the examples together with a XULRunner if you don't want to use firefox to run the application.

If you like Smalltalk and you develop Web Applications give it a try.

Nokia N96 (New IPhone Killer)

2008-05-15T13:49:00Z

I've seen a Nokia N95 and it's an incredible device. In early 2008, Nokia announced the N95 successor, the N96, many of the previous drawbacks were improved and new features came with this new IPhone Killer.

Even when many rumors of a new 3G Iphone appear every day (Some days ago a friend told me that Apple doesn't sell Iphones for the moment), Nokia continue announcing great mobile phones for the 2008. After giving the news of the N810, the N800 successor (I used to own a N800 and is an incredible device), the time for the new High end cellphone arrived (The N810 is not a Cellphone).

Here are some images of this incredible phone: <object type="text/html" height="500" width="500" data="http://www.flickr.com/slideShow/index.gne?user_id=23148115@N05&tags=n96"> </object>

The improvements of the N96 over the N95 are the following:

<en>Dimensions:</en>The N96 only a little bigger and heavier than is predecessor
Display: The display is 0.2" bigger in the N96 but it's still a QVGA (240 x 320 pixels) 16 million colour-capable LCD TFT.
Video and Imaging: The video support in the N96 is much more better and supports a wide variety of standard file formats, the Video recording and Camera are the same as in the N95. The N96 now gives access to Live TV, where DVB-H broadcasts are available.
Music: The only change here is the possibility to display album art.

Connectivity: The big plus here in the N96 Phone is assisted GPS feature.

Storage: This is one of the best things in the N96, now the memory is 16GB and it has a hot swappable microSD memory card slot.

NiiMe: Controlling games from a cellphone

2008-04-17T14:33:00Z
NiiMe is a software programed in Python that use the accelerometers built in some mobile phones (like N95, 5500, ...) These are some very interesting videos from youtube: <object height="355" width="425"><param name="movie" value="http://www.youtube.com/v/00PKV5xCL24&hl=en"></param><param name="wmode" value="transparent"></param><embed type="application/x-shockwave-flash" src="http://www.youtube.com/v/00PKV5xCL24&hl=en" height="355" wmode="transparent" width="425"></embed></object> All these new phone devices comes with very powerful sensors that makes this kind of applications.

Google App Engine

2008-04-09T13:10:00Z
A couple of days ago Google launched something called Google App Engine. In a nutshell it gives you the ability to develop applications using their infrastructure. For me, this is one of the most important announcements that Google made over the last time and even when it doesn't compete directly with Amazon's service it could become a competitor in some segments (mainly typical python web applications). I have some different thoughts about this launch and I think it has it pros and cons:

Pros:

It gives you the ability to program in a web environment with a very powerful OOP language as python.

It takes away the problem of clustering your application.

You can publish your application in their catalog.

The BigTable interface proved for them to be a good alternative to relational databases.

You will have plenty of examples from other developers using this framework

It provides some very usefull services as mail, storage, user management and url fetch to comunicate to other hosts

It comes with a local SDK environment to use it in your local computer

Cons:

You can't know what the cost of the service could be.

You can't get an account right now because they opened only 10.000 accounts and they are all taken (It reminds me to gmail early days)

The storage seems very little (only 500 Mb) for some kind of applications.

I don't know if this is the case but Google always builds it's own standard instead of using some widely used (GData Vs. Atom)

The Data API doesn't seems too nice (not better than elixir in Python or Active Record in Ruby)

Google has a secret plan to take over the world and this is a big step (controlling every application) :P

I think is a very good thing in general and it will give many developers to easily share and publish their work. It can be a very good way to start but I think you should take care not to be locked into this engine in order to maintain your ability to have your own servers. I'll try to do some tests and possibly develop soma application.

sky.google.com made in Argentina

2008-03-13T21:03:00Z

Argentinian winner of Google Code Jam developed the new Google Sky

From google blog:

"Diego Gavinowich from Buenos Aires was a finalist in our Latin America Code Jam, and joined us for a winter internship three months ago (missing summer break in Argentina!). Since he loves astronomy and web hacking, we gave Diego a new Code Jam challenge: code a web version of Google Sky by the end of his time with us."

It makes one happy to know that Argentinian talent is being shown at Google.

Paul Tuckfield - The youtube DBA

2008-03-03T09:00:00Z
Excelent video about youtube DBA explaining performance tuning and scalability stuff. The slides are missing so if anyone has them post a comment. <object allowfullscreen="true" type="application/x-shockwave-flash" id="showplayer" height="255" width="400" data="http://blip.tv/scripts/flash/showplayer.swf?enablejs=true&feedurl=http%3A%2F%2Fmysqlconf%2Eblip%2Etv%2Frss&file=http%3A%2F%2Fblip%2Etv%2Frss%2Fflash%2F543279&showplayerpath=http%3A%2F%2Fblip%2Etv%2Fscripts%2Fflash%2Fshowplayer%2Eswf"><param name="movie" value="http://blip.tv/scripts/flash/showplayer.swf?enablejs=true&feedurl=http%3A%2F%2Fmysqlconf%2Eblip%2Etv%2Frss&file=http%3A%2F%2Fblip%2Etv%2Frss%2Fflash%2F543279&showplayerpath=http%3A%2F%2Fblip%2Etv%2Fscripts%2Fflash%2Fshowplayer%2Eswf" /><param name="quality" value="best" /><embed name="showplayer" type="application/x-shockwave-flash" src="http://blip.tv/scripts/flash/showplayer.swf?enablejs=true&feedurl=http%3A%2F%2Fmysqlconf%2Eblip%2Etv%2Frss&file=http%3A%2F%2Fblip%2Etv%2Frss%2Fflash%2F543279&showplayerpath=http%3A%2F%2Fblip%2Etv%2Fscripts%2Fflash%2Fshowplayer%2Eswf" height="255" quality="best" width="400"></embed></object>
In this video you can see Paul Tuckfield, talk about how they scaled Youtube, some interesting points:

Things that made youtube scale:

Python

Caching (before getting to the DB)

DB tuning (that's what the video is about

From the DB tuning my highlights are these:

Views count goes to a MyIsam DB

Favourites, playlists, etc goes to a DB that thens replicates to other 5, as to divide the read queries

Slow replication is a very big problem and is difficult to keep replication fast.

InnoDB doesn't recover easily and is not nice to switch to the replica because you are not sure if that's OK.

You can test things in one replica and if it works pass that change to the rest of them.

A good trick is to have a replica with some lag as a way to have a easy restorable backup.

When migrating to 5.0 is better to dump and load instead of updating in place.

To upgrade hardware means much more memory and many disk drives (even if they are small) instead of fast CPUs and big hard drives

If it is on cache you are ok, if your database fits in cache, go to have a coffee

Write Cache is OK, Read Cache is BAD in levels below the database(Linux or RAID).

For parallel reads is better to have big chunks

At the last part of the talk he explains some very interesting algorithms to predict the things that must be in the cache of replicas achieving excelent results.

The importance of code reviews

2008-02-29T09:00:00Z
Sometimes we miss the importance of code reviews, sometimes we are not sure of how to make them.This post links to an example that even when you know this is impossible to happen where you work, gives you the idea that at least some ad-hoc code review could help finding strange things, doing some refactor, deleting dead code and avoiding un-useful documentation reducing the code base of the system.
I've found very interesting one post in thedailywtf that shows an incredible code that was discovered during an attempt to discover a random result of some system. The example is way to extreme and I think that it takes more than avoiding code reviews to get to this kind of code but extremes are very useful to show the importance of things, Here is the article, enjoy it as much as I did.

As I said in the excerpt, reviews tend to reduce your code base, making your system more mantenible, modifiable, helping debugging, bug fixing and increasing your productivity, apart from this kind of ugly code that I'm sure is difficult to find I places with good programmers all other benefits of code reviews are much more important overall.

An IEEE article from 1985

2008-02-26T12:01:00Z
I read recently this excelent IEEE article from 1985, I wanted to do some explanation about it but I'm having so little time that I don't know if I'll be going to do it, I took some quotes and leave you the link to read it.
One of the best parts about the articles is the characteristics that a manager should have, according to the autor:
Rules on choosing managers:

A good researcher is not automatically a good manager of people.

A good manager of people (for example, of salesman) is not automatically good at managing or administering a research group in science or technology.

Another important quote is
"The concept of PARC has been essentially a long-range strategic view. It is a critical attitude for good research..."
I'll try to complete this post with a better review about the article, but in the meanwhile I strongly recommend its reading.

Link al paper