News from the Distributed Storage World


There was a post running on the FUSE mailing list that captured my attention this week. A Google FS-like sort of distributed file system named Startfish.

In their FAQ, there are several claims (and bar charts) about good performance results regarding several performance metrics (i.e. read/write throughput, scalability, etc) compared to NFS, SAMBA and Lustre file systems. But, I think a deep evaluation seems to be needed to assess these claimed advantages.

Also, this seems to be a major milestone on the increasing number of FUSE-based file systems. It would be nice to try it out.

The Art of Tagging Libraries


It turns out that there is a system that allows users to tag virtual library catalogs.

Thanks to my fellows at OpenTag.

The system is called PennTags and it is developed by people at University of Pennsylvania.

The Art of Tagging


This seems a very interesting idea on how to extract the perception of public about objects, particularly, art works. Furthermore, it is also a clever way to understand what is the vocabulary actually used by the majority of the audience to describe the art works.

The Art Museum Social Tagging Project

There is a workshop paper about it in the program of WWW2006 Conference:

Investigating social tagging and folksonomy in art museums with steve.museum

An interesting application of the same idea would be to add tagging capabilities to online library catalogs, where users of public libraries could categorize items that they've read (or intend to) by using tags online. This could give a clue about the content of the item, a kind of highly compacted review.

Rethinking your role...


The BBC has published this article about a petition by European institutions requesting a that all government funded research should be easily available to the public - you can read the article here http://news.bbc.co.uk/2/hi/technology/6404429.stm.

Particularly, the idea of providing open access to government funded research publications seems a sensible move. However, the whole picture is a bit more complex, I guess. The article nicely points out what it may be the fundamental question regarding the discussion on "To Open or Not To Open", which is the role of researchers in disseminating information.

"High Fidelity"


A short break on popularity distributions and clustering coefficients.

The novel High Fidelity by Nick Hornby is guaranteed fun. The movie based on the novel, which is located at Chicago, is also great. I also must confess that I got the Top Five fever for a while after reading the book and watching the movie.

Thus, just for your fun consideration, appreciated reader, here is my top 5 ranking for cover versions of songs.

1. "Garota de Ipanema" by RUSH (originally by Tom Jobim and Vinicius de Moraes)
2. "What a wonderful world" by Joe Ramone (orginally by Louis Armstrong)
3. "Have a Cigar" performed by Foo Fighters (originally by Pink Floyd)
4. "Bullet in the Blue Sky" by Sepultura (originally by U2)
5. "Hurt" by Johnny Cash (originally by NIN)

Now, a nice place to find those songs... Hype Machine, a nice tool for search music and video content commented on blogs.

Enjoy,
Elizeu

Hemingway and FLP


Yesterday, I have finished reading For Whom the Bell Tolls by Ernest Hemingway. It is not only because the book is written by a Nobel Prize winner that it is worth reading, it is a very interesting and thought provoking book about the human nature. My impression is that the book becomes more and more exciting as it comes to the end.

Anyway, the main goal of this post is not solely discuss my impressions about this Hemingway's book. The fact is that for several chapters the main character faces a dilemma, which is in my opinion the same challenge faced by those building reliable distributed systems, this is explained by a great paper well known as - FLP. :-)

(Un)fortunately, Robert Jordan could not have access, at that time, to the ground breaking paper by Fisher, Lynch and Patterson (Impossibility of distributed consensus with one faulty process) to shed some light (or darkness, perhaps) on his situation.

Definitely, both works are great references...

The Power of Probability

An article published at Live Science defends the idea that it is possible that two snowflakes are alike. At least if you believe in probability.

The article says that it is possible to have two snowflakes alike, but with very low probability. Moreover, it totally depends on the way similarity is defined ( number of crystals and shape, for example).

So, be aware when you use the setence "no two snowflakes are alike".

For those who like macro photography, the pictures are very nice.

Zenit 12XP

A bit of photography now.

As a result of a complex conjunction events, I decided to use my first reflex camera again for a couple of weeks.

It might sound odd, but there is a kind of unique experience on handling a totally mechanic camera as opposed to a modern one (film or digital). From the film loading process, which is more like a ritual than a technical process, to the feeling-based exposure settings.

I've got very nice experimental results with this came in low light conditions. However, what impressed more was color saturation levels I got in a set of pictures.

There was an expedition where I took the same pictures with the Zenit 12XP and an EOS 300 (EOS Rebel in USA) with the same negative film, developed at the same place.

I was planning a set of photographs of urban landscapes with snow. Unfortunately, the shutter mechanism presented some problems in the first frames of a film last weekend. Incredible sunset light tones illuminating the buildings on my neighborhood, but the camera asked for a retirement.

Great times we had together!

BloggerFS

Last night I was playing around with FUSE, FUSE-J and Blogger Data API. The result is a new FUSE-based filesystem, which is named BloggerFS.

The idea is very simple, by using BloggerFS one can manipulate posts on her blog as if they were files. The user just need to pass a mounting point, a blog address (it needs to be on Blogger) and a pair username/password.

I intend to publish the source code under GPL as soon as the code is fairly documented and ready for use in production. It would be nice to hear your experiences when using it.

Cheers,
./Eli

Netherlands goes all digital

The government completely siwtched the analog television transmission to digital. The main reason was what surprised me: only 74,000 households will be directly affected by this shift.

According to the news, cable-TV represents 94% of the TV market in Netherlands. This is pointed as one more reason to increase the competition by expanding the coverage of digital TV.

To be able to receive the digital TV signal, users will have to buy a tuner which is estimated to cost around $66.50. In terms of costs, this seems to be much cheaper when comparing to the costs per household to maintain the "free" analog TV. The governement will save $200 per household (a year) with this shift according to the information published at Chron.com (link below).

It seems to me very interesting the role of people that need to think about new formats for TV shows, movies "made for TV", news, and so on, assuming a new technology to transmit them. I had a very inspiring converstion about how Video Art has changed the way people do TV shows, and way people think of doing a TV show is completely different fom cinema. Interestingly, a decisive aspect is the technology that is going to be used for recording and transmitting.

Source: http://www.chron.com/disp/story.mpl/headline/world/4393351.html

First Impressions of Supercomputing & VTCD'06

I guess this is a late post. However, I still think it is relevant to say some words about my impressions of Supercomputing Conference 2006 (SC'06).

The SC'06 was held in Tampa, FL this year. As my first time in the conference, I had a bit of expectation about how large the conference is. It was very good to see the mix of industry and academia there. The main challange maybe is to measure how the demand posed by industrial scale clients would be driving research labs and university efforts.

The First International Workshop on Virtualization Technology in Distributed Computing (VTDC'06) was held in conjunction with SC'06 and it was a great opportunity to meet researchers involved in virtualization technologies.

I have been most of the time attending to the technical sessions, where there were a lot of interesting works and conversations. Here is a small list of papers that I have found neat ideas and important findings:

• Sage A Weil et al. "CRUSH: Controlled, Scalable, Decentralized Placement of Replicated Data"



• Zheng Zhang et al. "CycleMeter: Detecting Fraudulent Peers in Internet Cycle Sharing"




• Sotomayor et al. " Overhead Matters: A Model for Virtual Resource Management". VTDC'06.



• David Wolinsky et al. "On the Design of Virtual Machine Sandboxes for Distributed Computing in WOWs"
  
  

Hopefully see you on SC'07...

Cheers,
./Eli

Citizen Collaborative Work

Recently, I have been reading some articles on policies and mechanisms for collaborative work on virtual environments like the Web and I have found some interesting works on reputation schemes to ameliorate the quality of collaboration on collaborative content production.

A while ago I came across an article by Tom Cross on First Monday (Puppy smoothies: Improving the reliability of open, collaborative wikis) which proposes a simple mechanism to allow users to identify parts of a Wiki article that it is not "mature" yet. The rationale behind the approach proposed by Cross is that texts that survive a sufficiently long period of iterative and collaborative editing process may be considered mature and accurate. Conversely, texts recently added may contain inaccuracies. So, readers should be aware of which part is still not mature.

Today I have found a site which promotes the collaborative content production, Bikely. The idea is to allow users to share their bike routes, to add comments and share information about these routes. Basically, a use case for a combination of Wiki and Google Maps. :-)

In that context, I was wondering about a mechanism which could improve the quality of information about routes and comments on routes. In my first thought, the assumption used by Cross may not apply here, since routes could be out of date over time in contrast to text that gets mature. It has also the case where routes and comments are misleading. Anyway, I believe this is a good motivation to think about a reputation scheme with a nice application.

By the way, check out my routes:

- Flamingo - UFCG (Campina Grande, PB, Brazil).
- Chesnut Park - UC Davis (Davis, CA, US)

Cheers,
Eli

"I read banned books"

I have seen a new post on the The Google Blog about a list of banned and challenged books from 20th century. It was nice to see that a lot of my favorite books are part of the list of best novels of the 20th century have been challenged or banned.

The interesting fact on that is that I do not usually decide about reading a book by magazine reviews and/or ranking of latest week's best sellers. I'd rather to collect good opinions in person talking to my friends. However, most of the time I discover good authors by 'accident' (by watching movies that refer some particular authors or by listening to some music which is inspired in some books). :-)

Furthermore, the list contains several books that I have already put on my shelf. Now, I was wondering what would be banned today ?

Keep reading! ;-)
./Eli

Fall is coming... Not really!

Alright, the Fall is almost coming, right? Not really. :-) I am in Brazil now and here Spring starts late this month. Thus, the inspiring summer days in Ryerson Hall at University of Chicago working in collaboration with Kate Keahey from Argonne National Labs as part of an internship are behind now.

However, we will be able to remember our wonderful conversation about Shakespeare and Tom Stoppard plays, since our paper was accepted in the Supercomputing'06. The work is entitled To Bid or Not To Bid: A Hybrid Market-Based Resource Allocation Framework. Actually, talking about those authors was motivated by the title that I suggested to the paper. I almost included 'Arcadia' and 'Romeo & Juliet' in the references. :-)

Now, I am part of the LSD-family (Laboratorio de Sistemas Distribuidos) again, at least for the next 4 months. The idea is to be involved with the same research topics that I have been looking into during the summer season at Chicago, but the application is different. The goals is to improve the virtualization solution provided by the OurGrid. I am very glad to be here after one year away to meet my former advisors and friends.

So, I'm looking forward to be in the Supercomputing in November. I hope to see most of my friends from Chicago there. Making new friends is part of the plan as well. :-)

Cheers,
Eli

Lollapalooza Days

This might seem off topic. However, I would like to comment on my experience at Lollapalooza.

I had the great opportunity to go to Lollapalooza last weekend. The festival was located in Grant Park at Downtown Chicago. I long list of bands played during three days of a good (sometimes, not so good) rhythm mixture.

Lollapalooza was probably the biggest music festival that I have been so far. I would say that the second in size was the Rock In Rio III (Rio de Janeiro, Brazil). The infrastructure of Lollapalooza was perfect, my only complaint was the fact that they were not selling beer, only Budweiser. :-) The concerts were perfectly scheduled and I really enjoyed the whole environment around Grant Park and Downtown.

Last Monday, a friend sent an article from MIT Technology Review about Technology @ Lollapalooza. This is just one more example that networked technology is part of our daily lives.

Despite the fact that the technology device that I took more advantage was a portable fan with an attached water mister during the very very hot weather on Friday, it was interesting to see the high-tech tends packed.

I was wondering later that one could enjoy this huge live crowd to perform a kind of field experiment with sensor devices attached to people. Perhaps, some of the collected data in this "live experiment" could be useful for future simulation based studies.

The Backup Power

The fact that backup is an important part of any IT infrastructure management plan, everybody should know. What about backing up DNAs?

Well, this is what a NYTimes article by By Richard Morgan ("Life After Earth: Imagining Survival Beyond This Terra Firma") suggests (in a scientific fiction mode) that it could be done to prevent human life of being extinct by natural or war disasters.

Despite the currently unrealistic, yet possible, interesting description of the applicability of a DNA repository of every form of life in our beloved planet earth, the article discuss how the doomsday is understated sometimes.

However, instead of putting all effort on developing technologies for "DNA backup" and storage, how about to move the focus from military development to sustainable development? I guess this would be a very good and true step to reduce the risk of human extinction.

Anyway, reading this article was good to reassure my point of view that some priorities of some nations do not seem to me the right way to go. :-)

Cheers,
./Eli

Greenwood Simulator

It's been a long time, since the last time I've posted. Alright, I guess I'll have more time for the rest of the summer to post some interesting thought about what really matters in life: People, Music, Photography and Computers. :-)

The good news is that I have started a new solo project last Spring. After having a laptop crash I decided to publish the partially recovered source code that I have been developing under the terms of an open source initiative.

The main goal is to develop a simulator (or something more like a simulation framework) to help researchers interested in having fun with data staging on large scale and distributed storage environments.

GreenSim builds on top of Simgrid Toolkit. My main goal is to provide a developer-oriented framework that can be personalized to specific demands.

However, before downloading you should be aware that the software is still in a pre-alpha version. Thus, you should not expect a stable version. I will keep committing changes, bug fixes and announcing releases here, as soon as the internship activities allow me to do.

In the case you feel interested in participate, please, drop me a message and let's discuss your ideas, I would appreciate it!

GreenSim
http://greensim.sourceforge.net

Regards,
./Eli

Is Computer Science a science?

Time to time this question comes to my mind, and (almost automatically) I remember a statement by one of the most interesting persons that I have met in Chicago while we were enjoying some beers with our advisor:

"Real sciences do not need to have the word science in their names. For example, Physics, Biology and Chemistry."

I should start this post by saying that I disagree with such statement. :-)

Let us take a look at what is the definition of the word science According to the Merrian-Webster Online (http://www.m-w.com). Thus, we have:


1: the state of knowing : knowledge as distinguished from ignorance or misunderstanding

2 a : a department of systematized knowledge as an object of study (the science of theology) b : something (as a sport or technique) that may be studied or learned like systematized knowledge (have it down to a science)

3 a : knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method b : such knowledge or such a system of knowledge concerned with the physical world and its phenomena : NATURAL SCIENCE

4 : a system or method reconciling practical ends with scientific laws (culinary science)


To avoid being biased and a situation where one could tell me that I do not know the color of the sky. I will cite a second source. No, the second source is not Britanica, it is Wikipedia (http://en.wikipedia.org/wiki/Science).


[...]
refers to the system of acquiring knowledge based on empiricism, experimentation, and methodological naturalism.
[...]


Therefore, I think that Computer Science fits very well on both definitions and it should be considered a real science. Perhaps a good next question is: what is a good scientific method in computer science and what is not?

However, this is a discussion for a second round of beers. :-)

Cheers,
Eli

The Spam World Map

I have found an interesting tool based on the Google Maps API and Host IP Info API. The tool basically translates domain names to a geographic location by showing on the map. The idea is pretty simple. But it is nice. :-)

Here is the link: http://map.butterfat.net/emailroutemap/

It was a very interesting finding because some days ago I was poetically thinking about exploiting geographical location and network information/usage patterns for some particular cases that I am investigating now. One of the results that I am particularly aware are related to a time zone aware scheduling approach.

Cheers,
Eli

IP Design Principles

Recently, I have found a very interesting article that revisited a discussion on the IP packet switching foundations versus circuit switching.

I particularly liked the article structure and agree with some points exposed by the authors. Mainly, the question whether there is an approach to guarantee non-trivial QoS levels over IP other than overprovisioning the links.

Yet, the most important aspect in the article is the attempt to uncurtain new perspectives for packet switching and circuit switching as well.

The paper is short, contains good references and it is definitely worth reading.

Is IP going to take over the world (of communications)?

Regards,
Eli