Discussion of Facebook’s data management technologies. Related subjects include:
- Cassandra, which was originated at Facebook
- Hadoop, one of whose largest supporters is Facebook
- Google’s data management technologies
- Amazon’s data management technologies
Privacy dangers — an overview
This post is the first of a series. The second one delves into the technology behind the most serious electronic privacy threats.
The privacy discussion has gotten more active, and more complicated as well. A year ago, I still struggled to get people to pay attention to privacy concerns at all, at least in the United States, with my first public breakthrough coming at the end of January. But much has changed since then.
On the commercial side, Facebook modified its privacy policies, garnering great press attention and an intense user backlash, leading to a quick partial retreat. The Wall Street Journal then launched a long series of articles — 13 so far — recounting multiple kinds of privacy threats. Other media joined in, from Forbes to CNet. Various forms of US government rule-making to inhibit advertising-related tracking have been proposed as an apparent result.
In the US, the government had a lively year as well. The Transportation Security Administration (TSA) rolled out what have been dubbed “porn scanners,” and backed them up with “enhanced patdowns.” For somebody who is, for example, female, young, a sex abuse survivor, and/or a follower of certain religions, those can be highly unpleasant, if not traumatic. Meanwhile, the Wikileaks/Cablegate events have spawned a government reaction whose scope is only beginning to be seen. A couple of “highlights” so far are some very nasty laptop seizures, and the recent demand for information on over 600,000 Twitter accounts. (Christopher Soghoian provided a detailed, nuanced legal analysis of same.)
At this point, it’s fair to say there are at least six different kinds of legitimate privacy fear. Read more
| Categories: Analytic technologies, Facebook, GIS and geospatial, Health care, Surveillance and privacy, Telecommunications, Web analytics | 6 Comments |
More on NoSQL and HVSP (or OLRP)
Since posting last Wednesday morning that I’m looking into NoSQL and HVSP, I’ve had a lot of conversations, including with (among others):
- Dwight Merriman of 10gen (MongoDB)
- Damien Katz of Couchio (CouchDB)
- Matt Pfeil of Riptano (Cassandra)
- Todd Lipcon of Cloudera (HBase committer)
- Tony Falco of Basho (Riak)
- John Busch of Schooner
- Ori Herrnstadt of Akiban
I’m collecting data points on NoSQL and HVSP adoption
I was asked to do a magazine article on NoSQL, where by “NoSQL” is meant “whatever they talk about at NoSQL conferences.” By now the number of publications planning to run the article is up to 2, the deadline is next week and, crucially, it has been agreed that I may talk about HVSP in general, NoSQL and SQL alike.
It also is understood that, realistically, I can’t be expected to know and mention the very latest news for all the many products in the categories. Even so, I think this would be fine time to check just where NoSQL and HVSP adoption stand. Here is most of what I know, or links to same; it would be great if you guys would contribute additional data in the comment thread.
In the NoSQL area: Read more
Links and observations
I’m back from a trip to the SF Bay area, with a lot of writing ahead of me. I’ll dive in with some quick comments here, then write at greater length about some of these points when I can. From my trip: Read more
| Categories: Analytic technologies, Aster Data, Calpont, Cassandra, Couchbase, Data warehouse appliances, Data warehousing, EMC, Exadata, Facebook, Greenplum, HP and Neoview, Kickfire, NoSQL, OLTP, ParAccel, Sybase, XtremeData | 1 Comment |
Nested data structures keep coming up, especially for log files
Nested data structures have come up several times now, almost always in the context of log files.
- Google has published about a project called Dremel. Per Tasso Agyros, one of Dremel’s key concepts is nested data structures.
- Those arrays that the XLDB/SciDB folks keep talking about are meant to be nested data structures. Scientific data is of course log-oriented. eBay was very interested in that project too.
- Facebook’s log files have a big nested data structure flavor.
I don’t have a grasp yet on what exactly is happening here, but it’s something.
| Categories: eBay, Facebook, Google, Log analysis, Scientific research, Theory and architecture | 7 Comments |
dbShards — a lot like an MPP OLTP DBMS based on MySQL or PostgreSQL
I talked yesterday w/ Cory Isaacson, who runs CodeFutures, makers of dbShards. dbShards is a software layer that turns an ordinary DBMS (currently MySQL or PostgreSQL) into an MPP shared-nothing ACID-compliant OLTP DBMS. Technical highlights included: Read more
| Categories: dbShards and CodeFutures, Facebook, MySQL, OLTP, Parallelization, PostgreSQL | 3 Comments |
Riptano, and Cassandra adoption
Tonight’s Cassandra technology post got plenty long enough on its own, so I’m separating out business and adoption issues here. For starters, known Cassandra users include:
- Facebook, which has said it has 150 or so Cassandra nodes (but see below)
- Twitter, which has said it has 45 or so Cassandra nodes
- Rackspace, which used to be Jonathan Ellis’ employer, and now is backing Cassandra company Riptano
- Digg, which along with Twitter and Rackspace was one of the three major users helping advance the Cassandra project
- OpenX, Simple Geo, Digital Reasoning, who Jonathan cited as production users in March
- Cloudkick, as noted and linked in my other post
- Two customers Riptano named at launch (but I’ve forgotten who they were*)
Fetlife, Meebo, and others seem to at least have a healthy interest in Cassandra, based on their level of involvement in a forthcoming Cassandra Summit. That said, the @Fetlife tweetstream features numerous yelps of pain, and I don’t mean the recreational kind. Read more
| Categories: Cassandra, DataStax, Facebook, Market share and customer counts, NoSQL, Open source, Parallelization, Pricing, Specific users | 5 Comments |
Cassandra technical overview
Back in March, I talked with Jonathan Ellis of Rackspace, who runs the Apache Cassandra project. I started drafting a blog post then, but never put it up. Then Jonathan cofounded Riptano, a company to commercialize Cassandra, and so I talked with him again in May. Well, I’m finally finding time to clear my Cassandra/Riptano backlog. I’ll cover the more technical parts below, and the more business- or usage-oriented ones in a companion Cassandra/Riptano post.
Jonathan’s core claims for Cassandra include:
- Cassandra is shared-nothing.
- Cassandra has good approaches to replication and partitioning, right out of the box.
- In particular, Cassandra is good for use cases that distribute a database around the world and want to access it at “local” latencies. (Indeed, Jonathan asserts that non-local replication is a significant non-big-data Cassandra use case.)
- Cassandra’s scale-out is application-transparent, unlike sharded MySQL’s.
- Cassandra is fast at both appends and range queries, which would be hard to accomplish in a pure key-value store.
In general, Jonathan positions Cassandra as being best-suited to handle a small number of operations at high volume, throughput, and speed. The rest of what you do, as far as he’s concerned, may well belong in a more traditional SQL DBMS. Read more
| Categories: Amazon and its cloud, Cassandra, DataStax, Facebook, Google, Log analysis, NoSQL, Open source, Parallelization | 4 Comments |
The most important part of the “social graph” is neither social nor a graph
“Social graph” is a highly misleading term, and so is “social network analysis.” By this I mean:
There’s something akin to “social graphs” and “social network analysis” that is more or less worthy of all the current hype – but graphs and network analysis are only a minor part of the whole story.
In particular, the most important parts of the Facebook “social graph” are neither social nor a graph. Rather, what’s really important is an aggregate Profile of Revealed Preferences, of which person-to-person connections or other things best modeled by a graph play only a small part.
| Categories: Analytic technologies, Facebook, Games and virtual worlds, RDF and graphs, Surveillance and privacy, Web analytics | 13 Comments |
Information found in public-facing social networks
Here are some examples illustrating two recent themes of mine, namely:
- Easily-available information reveals all sorts of things about us.
- Graph-based analysis is on the rise.
Pete Warden scraped all of Facebook’s social graph (at least for the United States), and put up a really interesting-looking visualization of same. Facebook’s lawyer’s came down on him, and he quickly agreed to destroy the data he’d scraped, but also published ideas on how other people could duplicate his work.
Warden has since given an interview in which he outlines some of the things researchers hoped to do with this data: Read more
| Categories: Analytic technologies, Facebook, RDF and graphs, Surveillance and privacy | 1 Comment |