A small and fun experiment is out:
About 1 year after development started in Ensemble, today the stars finally aligned just the right way (review queue mostly empty, no other pressing needs, etc) for me to start writing the specification about the repository system we’ve been jointly planning for a long time. This is the system that the Ensemble client will communicate with for discovering which formulas are available, for publishing new formulas, for obtaining formula files for deployment, and so on.
One more Go library oriented towards building distributed systems hot off the presses: govclock. This one offers full vector clock support for the Go language. Vector clocks allow recording and analyzing the inherent partial ordering of events in a distributed system in a comfortable way.
The following features are offered by govclock, in addition to basic event tracking:
A bit of history
I don’t know exactly why, but I’ve always enjoyed IRC bots. Perhaps it’s the fact that it emulates a person in an easy-to-program way, or maybe it’s about having a flexible and shared “command line” tool, or maybe it’s just the fact that it helps people perceive things in an asynchronous way without much effort. Probably a bit of everything, actually.
Scott Moser has just announced this week that the new Ubuntu images which boot out of an EBS-based root filesystem in EC2, and thus will persist across reboots, are available for testing.
As usual with something that just left the oven and is explicitly labeled for testing purposes, there was a minor bug in the first iteration of images which was even mentioned in the announcement itself. The bug, if not worked around as specified in the announcement, will prevent the image from rebooting.
Having an bootable EBS image which can’t reboot is a quite interesting (and ironic) problem. You have an image which persists, but suddenly you have no way to see what is inside the image anymore because you can’t boot it. Naturally, even if the said bug didn’t exist in the first place, it’s fairly easy to get into such a situation accidentally if you’re fiddling with the image configuration.
So, in this post we’ll see how to recover from a situation where a bootable EBS image can’t boot.
Some interesting changes have been happening in my professional life, so I wanted to share it here to update friends and also for me to keep track of things over time (at some point I will be older and will certainly laugh at what I called “interesting changes” in the ol’days). Given the goal, I apologize but this may come across as more egocentric than usual, so please feel free to jump over to your next blog post at any time.
It was already dead. In some senses, anyway.
Google announced a couple of days ago that they’re advancing into the business of GPS guided navigation, rather than staying with their widely popular offering of mapping and positioning only. This announcement affected the rest of the industry immediately, and some of the industry leaders in the area have quickly taken a hit on their share value.
As usual, Slashdot caught up on the news and asked the question: Will Google and Android kill standalone GPS?
Let me point out that the way the facts were covered by Slashdot was quite misguided. Google may be giving a hand to change the industry dynamics a bit faster, but both Garmin and TomTom, the companies which reportedly had an impact in their share value, have phone-based offerings of their own, so it’s not like Google suddenly had an idea for creating a phone-based navigation software which will replace every other offering. The world is slowly converging towards a multi-purpose device for quite a while, and these multi-purpose devices are putting GPSes in the hands of people that in many cases never considered buying a GPS.
The real reason why these companies are taking a hit in their shares now is because Google announced it will offer for free something that these companies charge quality money for at the moment, being it in a standalone GPS or not.
More than 40 years ago, a guy named Douglas Parkhill described the concept of utility computing. He described it as containing features such as:
- Essentially simultaneous use of the system by many remote users.
- Concurrent running of different multiple programs.
- Availability of at least the same range of facilities and capabilities at the remote stations as the user would expect if he where the sole operator of a private computer.
- A system of charging based upon a flat service charge and a variable charge based on usage.
- Capacity for indefinite growth, so that as the customer load increases, the system can expanded without limit by various means.
Fast forward 40 years, and we now name pretty much this same concept as Cloud Computing, and everyone is very excited about the possibilities that exist within this new world. Different companies are pushing this idea in different ways. One of the pioneers in that area is of course Amazon, which managed to create a quite good public cloud offering through their Amazon Web Services product.