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wicknicks

2,343 karma · joined January 17, 2009

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wicknicks··on How CockroachDB Does Distributed, Atomic Transactions
Yeah, I am not sure how multiple queries will co-exist in this strategy. Especially, if you have two queries which are not commutative (say, one which increments a column and the other one which replaces the column with its square root).

Also, how does this work in the presence of replicas? Does every replica go through the strategy? What if one or more replicas go down during a transaction?

wicknicks··on Coding for SSDs
The fact that we can do parallel reads from an SSD does give more flexibility to DB developers.
wicknicks··on MongoDB and RocksDB at Parse
I'm going to provide basic answers here. You can look at the homepage for more detailed answers (the video linked there is very helpful too) [1].

Main use case: Multi-threaded low latency data access. It is optimized for use cases where the insert/update rate is very high. In short, it has an LSM tree to quickly add new/updated records. At frequent intervals this LSM tree is merged into the on-disk pages. It is very well engineered, making the lookups very fast as well.

Queries can touch data on disk as well.

Rocks is an embedded database. Natively written in C++, but has bindings for other languages. [2]

No, nodes do not talk to each other.

Something I am personally excited about: RocksDB has a merge operator, which is (probably) still in development. It allows you to update the value of an entry by providing a merge function. It is extremely useful to merge data if you binary format supports it (for example, protobufs do this natively, and it will be very smart to store your protobuf binary natively in Rocks, and do regular merges to it).

No, an in-memory dictionary will provide far fewer guarantees and features.

[1] http://rocksdb.org/

[2] https://github.com/facebook/rocksdb/wiki/Third-party-languag...

wicknicks··on Where do the wealthiest 1% live?
Germany with 2.8 million is equally interesting. The country's population is 80m. Atleast one in 35 people there is in the top 1%.
wicknicks··on Ask HN: What should I save for offline reading during 5 weeks without Internet?
It depends on personal taste. But if I were going to a country I never visited before, there would be very little time to do anything else other than sightseeing, mingling with the locals, learning about their culture, their history, the food, and if you are anywhere near one, visit the national parks and take the safari.

Document everything you see. Take a good camera with you, and if you don't know how to use an SLR, this is the perfect time to learn some basic tricks. Once you pick a camera, you can find some tutorial on the web, which teaches you the basics for that brand/model.

I would use this time out to "take a break" from computer science. But if you can't stay away from it, pick up a book like SICP (http://mitpress.mit.edu/sicp/). This is one of those books which you want to read away from all distractions and think deeply about. If you can, download the accompanying video lectures:

http://ocw.mit.edu/courses/electrical-engineering-and-comput...

wicknicks··on Transit – A format for conveying values between different languages
I couldn't find any documentation about it, but is there any way to achieve forward/backward compatibility with Transit?
wicknicks··on Java 8 Features
Yeah, I hope I am interpreting this the wrong the way. But instead of doing

  X.getA().getB().getC().getD()
we have to

   X.flatMap(X::getA)
    .flatMap(X::getB)
    .map(X::getC)
    .orElse("UNKNOWN");  //[1]
Not sure why this is going to be better?

[1] http://www.oracle.com/technetwork/articles/java/java8-option...

wicknicks··on Why air travel hasn't gotten any faster since the 1960s
The problem is not to to just get from point A to B, but to have a good experience doing it. Air travel is getting worse every year. Starting from the airport checks to the long immigration lines (when traveling internationally) and super expensive fares for those "cuddly" seats, it can make holidays more exhausting than work. And if you live an hour from the airport, well good luck!

My idea of a grand future is when we can travel across the globe in less than hour, and pay less than $50 doing it.

wicknicks··on Leslie Lamport awarded Turing Award
The above link is a summary to the paper. Here is the actual publication: http://cnlab.kaist.ac.kr/~ikjun/data/Course_work/CS642-Distr...
wicknicks··on Programming is a Terrible Job
> The world is wide open to you.

In the United States probably. The author doesn't sound too old, and says that he/she got access to the internet much later. Which means the author is probably from the Middle east or China or South Asia. The work culture there is not as open as in the west. Daily job means monotonous routine work. What excited him about the prime numbers problem was the novel aspect of it, and the fact that he was in control. Later, in his/her day job, that was no longer the case -- someone else was making the decisions. Until these nuances trickle into daily jobs, most people will sooner than later burnout.

wicknicks··on Go Hadoop: Err, Hadoop and Go
Took me a while to figure it out too. I think the title would have been best written as "Hadoop and Go".

Its maybe because I'm new to the language, but I have to add 'lang' to all my Google searches for Go documentation/tips, otherwise the keywords are almost always misinterpreted.

wicknicks··on Rich Hickey's Greatest Hits
Rich Hickey is a genius. I love how he connected music to software engineering [1]. He should write a book on some of these topics. He has a lot more than 45 mins talks to offer to the world.

[1] http://www.infoq.com/presentations/Design-Composition-Perfor...

wicknicks··on RethinkDB 1.9: Indexing and query runtime performance
You should give it a try. RethinkDB, imo, embraces a lot of good ideas from the SQL world. Given a few years, I feel they will have a great DB with good ideas from both the SQL and NoSQL worlds.
wicknicks··on Ask HN: How to best acquire theoretical computer science knowledge?
A precursor to the compilers class is the Formal Automata one. This is very useful in understanding fundamental computation models (what is computation, why, how can we do it etc..). I was recently reading [1] to refresh some concepts and found it to be more engaging than some of the older books on the topic.

[1] http://www.valorebooks.com/textbooks/automata-theory-and-app...

wicknicks··on Kindle MatchBook
Can't wait for this feature. I am wondering if they would do the opposite: Offer paper books for a lower price to customers who own the kindle?
wicknicks··on Android KitKat
Reminds me of this XKCD http://xkcd.com/927/
wicknicks··on Google is defragging Android
The video game community might misinterpret it:

http://en.wikipedia.org/wiki/Frag_%28video_gaming%29

wicknicks··on Nphysics – 2 and 3-dimensional rigid body physics engine in pure Rust
I'm hoping for a not-that-far future ... Jokes apart, does Rust perform as well as C++?
wicknicks··on Quickly go back to a directory instead of typing cd ../../..
Smart idea. Good job! Could you extend bd to jump to bookmarked directories. I often jump between /data... and ~/dir/containing/code/ -- would be useful to have one command help with both scenarios.
wicknicks··on The Face Scan Arrives
Very interesting technology. I used your website, uploaded three pictures -- it failed on the first, and worked somewhat on the others. I'm guessing it needs a more experienced user base? Assuming that model generation requires human supervision, do you think the neural network algorithm scales to the numbers mentioned in the article (trained on 12 million photos, and operating in 7 different states)?

BTW, all the best with your website. Hope you take more avatars "where go where no man has gone before!"

wicknicks··on The Face Scan Arrives
I didn't realize that. Got my passport long ago, and for the driving license I'm sure they just took a picture. There was no scan (atleast nothing like the laser scan described by bsenftner above).
wicknicks··on The Face Scan Arrives
Do you have any papers on your work? Would be great if you add a link to them.
wicknicks··on The Face Scan Arrives
Does anyone know how this can be technically achieved? Large scale face recognition with 1 photo per person in the training set?
wicknicks··on Microsoft’s best hope after Ballmer? A break up
Maybe have a common pool of resources from which they draw from. That would force the "weaker" companies to compete more or pivot to create better products.
wicknicks··on Show HN: Popped At, my many, many weekends realtime photo project
Cool project! Here are a couple of suggestions which may help me as a user better understand the "breaking events, popular trends, cultural attitudes, and individual expression":

1. If photos have a hashtag, display it alongside an image. Text is the underestimated medium of non-personal image interpretation. Especially, when the data rate is so high, there needs to be some more precise clue about what the images are actually trying to convey.

2. Aggregate photos with similar intent. Group them into a box or color code their borders. Many tweets have GPS tags. Use them to provide a map interface to either filter some or just add a tag indicating the place of origin.

3. Most people who can only read 2-3 languages, and tweets in other languages will be treated as noise, no matter how relevant. The only alternative is combine them with a similar tweet in a language the user can understand.

4. Is there any reason photos change randomly across cells, and not in any order (as compared to say raster scanning the table and replacing photos)? Personally think that changing photos in some order is less painful on the eyes. I get the feeling that I am missing out an a lot of content because of this. Maybe replace only one section of the table at at time?

Good luck!

wicknicks··on Linux 3.9 introduced a new way of writing socket servers
I imagine production servers would run monitoring processes to remove such "listening bugs".
wicknicks··on [dead]
Interesting to see two contrasting articles on the same day: http://www.independent.co.uk/life-style/gadgets-and-tech/new...
wicknicks··on Scientist Finds PageRank-Type Algorithm from the 1940s
Exactly. Page and Brin cite some papers (or atleast Kleinberg's paper does -- which inspired Pagerank) which deal with ranking authors based on their citation graph. This article makes no sense whatsoever.
wicknicks··on Code For India
That was shot down quite fast. I would give them a few months before making such a judgement.
wicknicks··on A Look Inside Our 210TB 2012 Web Corpus
I loved the inter-lingual web page linkage visualization project. Any idea why Traitor won the contest? It seems very similar to regular "create inverted index with map reduce" problem, or am I missing something?
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