Showing posts with label distributed systems. Show all posts
Showing posts with label distributed systems. Show all posts

Tuesday, February 25, 2014

What are some good resources for learning about distributed computing? Why?

Answer by Alex Kamil:
Prerequisites

Courses


Notes
Other:
MapReduce: What's the best way to come up to speed on MapReduce, Hadoop, and Hive? )
  • Learn about Google technology stack (MapReduce, BigTable, Dremel, Pregel, GFS, Chubby, Protobuf, Snappy, Ganeti, Tenzing, Sawzall, BigQuery, F1, Spanner, Jingle, GCM, Google Talk, etc). (See
Google Research: What are the most interesting Google Research papers?
also  http://www.columbia.edu/~ak2834/... , http://www.cs.rutgers.edu/~muthu... , http://the-paper-trail.org/blog/...)
  • Setup account with Amazon AWS/EC2/S3/EBS and experiment with running Hadoop on a cluster with large data sets (you can use Cloudera or YDN images, but in my opinion you can better understand the system if you set it up from scratch, using the original distribution). Watch the costs: http://www.networkworld.com/news...
What are some promising open-source alternatives to Hadoop MapReduce for map/reduce?)
(This is a live list. Edits and additions welcome)
View Answer on Quora

Monday, February 3, 2014

Eventual consistency in simple terms

Unless you live under a rock, you know 15 minutes can save you 15% and big data is going to make life super awesome!

I don't know if GEICO has consistency issues but big data does and I get the feeling the IT media and software vendors are trying to hide that under a rock.

Big data does a few things really well.  Specifically, write data and scale.  Sounds awesome, huh?  Well, hold on.  In order to do this it has many, many copies of the data stored all over the place.  Sometimes the copy A is updated and sometimes copy B is updated.  The point is to be able to write data at amazing scale and speed and distributing the data all over the place achieves this very difficult task.

But, but ...


Don't worry, eventually these copies of data are synchronized to represent a single version of the truth.

But, but ...

The word eventually scare you?  It should.  You see, in order to write data at all times and scale infinitely, something had to give.  That something is the synchronization of distributed data.




Put simply, big data distributes multiple copies of a database, writes to whichever copy is available and synchronizes the data when it can.



What the ...


I know, right?  I'm curious if there is a distributed system out there that has ever reached consistency.  If the point is to write at all costs because you have such a high volume of updates, when is there time to synchronize?


For those who prefer a more technical definition of eventual consistency:


Eventual consistency is a consistency model used in distributed computing that informally guarantees that, if no new updates are made to a given data item, eventually all accesses to that item will return the last updated value.[1]


How does this necessity of invention sit with you?


[polldaddy poll=7768766]

Thursday, September 26, 2013

Would you read my Big Data book?

As you my know, I am pretty critical of the "big data" hype in the information technology media.  One of my criticisms is the very term "big data".  Frankly, I hate the term as much as I hate the outrageous claims that are out there.

I prefer to talk about distributed systems which is really the differentiator in this space, in my humble [ref] degrees of humility can easily be argued[/ref] opinion.

As I researched distributed systems (DS), I came across a topic that struck a chord with my passion for data quality.  The topic was the CAP Theorem and notion of eventual consistency.  At this point, I am becoming obsessed with the notion of eventual consistency.

As a result, I am convinced I need to write a book on the topic and its implications on deploying distributed systems to a business and its decisions.

However, before I get too far down the line, I want to know is ...

would you read my book about eventual consistency and how that would impact a distributed system's ability to aid in the process of making business decisions?



Please vote and let me know!
[polldaddy poll=7427832]

What data quality is (and what it is not)

Like the radar system pictured above, data quality is a sentinel; a detection system put in place to warn of threats to valuable assets. ...