February 2017 Articles

stative |ˈstādiv| Linguistics

(of a verb) expressing a state or condition rather than an activity or event, such as be or know, as opposed to run or grow. Contrasted with dynamic

a stative verb.

mid 17th century: from Latin stativus, from stat- ‘stopped, standing,’ from the verb stare.

After nearly 13 years in orbit around Saturn, NASA’s Cassini spacecraft is now preparing for its “Grand Finale.” In April of 2017, Cassini will begin a series of dives between the gas giant’s cloudtops and the inner rings–on its way to a fiery end when it burns up in Saturn’s atmosphere on September 15. As scientists prepare for a new flood of never-before-seen images, a look back at some recent (and fairly recent) images of the Saturnian system taken by Cassini.

Incredible pictures.

In 1904, workers installed the first telescope at the still uncompleted Mt. Wilson Observatory. For much of the 20th century, astronomers with names like Hale and Hubble used it and the new telescopes it sprouted – the 100-inch reflector and three solar telescopes followed the initial 60-incher – as a figurative launch pad for exploration that changed our understanding of the cosmos.

Gradually, though, financial support waned along with the observatory’s cutting-edge status, and for the last 20 years its telescopes, still impressive by any standard, rely on the kind attention of a small volunteer team of retired space industry electrical engineers, most now in their 70s and 80s.

Instapaper, former owned and developed by Marco Arment, recently had a major outage due to database limitations. Coincidentally, Marco recently posted about Automatically test[ing] your database backups. Brian Donohue, Director of Engineering for Instapaper, wrote a good technical overview for web developers and backend engineers on Medium about the incident titled Instapaper Outage Cause & Recovery

The critical system that failed was our MySQL database, which we run as a hosted solution on Amazon’s Relational Database Service (RDS)…

Root cause

In short, the data failure was caused by a 2TB file size limit for RDS instances created before April 2014. On Wednesday, February 9 at 12:30PM PT our “bookmarks” table that stores articles saved by Instapaper users exceeded the 2TB file size limit. Subsequent attempts to insert new entries into the bookmarks table began to throw the following error:

OperationalError: (OperationalError) (1114, “The table ‘bookmarks’ is full”)

The reason this limitation exists is because MySQL RDS instances created before April 2014 used an ext3 filesystem which has a 2TB file size limit. Instances created after April 2014 are backed by an ext4 filesystem and subject to a 64TB file size limit.