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Submission Cassandra rewritten in C++, ten times faster 1

urdak writes: At Cassandra Summit opening today, Avi Kivity and Dor Laor (who had previously written KVM and OSv) announced ScyllaDB — an open-source C++ rewrite of Cassandra, the popular NoSQL database. ScyllaDB claims to achieve a whopping 10 times more throughput per node than the original Java code, with sub-millisecond 99%ile latency. They even measured 1 million transactions per second on a single node. The performance of the new code is attributed to writing it in Seastar — a C++ framework for writing complex asynchronous applications with optimal performance on modern hardware.

Submission New operating system sets out to replace Linux on the cloud

urdak writes: Today in CloudOpen in New Orleans, KVM veterans Avi Kivity and Dor Laor revealed their latest venture, a new open-source (BSD license) operating system named OSv. OSv can run existing Linux programs and runtime environments such as a JVM, but unlike Linux, OSv was designed from the ground up to run efficiently on virtual machines. For example, OSv avoids the traditional (but slow) userspace-kernel isolation, as on the cloud VMs normally run a single application. OSv is also much smaller than Linux, and breaks away from tradition by being written in C++11 (the language choice is explained in in this post).

Comment Re:Perfect analogy for NASA (Score 1) 184

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Comment Re:Perfect analogy for NASA (Score 1) 184


For every step of aviation history there was an economic or military justification. Sometimes advances were carried out for national ego justification (e.g. the Concorde), but without economic justification, it could not be sustained and technology reverted a step back.

Space is in the same position. There is economic justification for commercial satellites, but no economic justification for the manned space program (or for the unmanned science and exploration program, but don't tell anyone). That is why we haven't been to the moon again and that is why the ISS will eventually be deorbited.

The problems of space travel are real. It takes huge amount of energy and labour to get something into orbit, and even more to get a human there and keep him alive. And what do you get in return? NOTHING.

Comment Re:Perfect analogy for NASA (Score 1) 184

And the mammals did?

The dinosaurs are extinct because they didn't adapt to a changing environment. With technology and science, we're a lot more adaptable than any other animal. In fact you can find us everywhere on earth, as well as in space.


Robot Dominates Air Hockey, Adapts To Opponents' Playing Style 49

colinneagle writes "Researchers at Chiba University in Japan have developed a robot that could frustrate teenagers worldwide with its impressive air hockey skills. What's remarkable about this air hockey-playing robot, which is not the first of its kind, is that it can sense human opponents' playing styles and adapt to defend against them. The key is how the computer controlling the robot views its opponent — at a speed of 500 frames per second. From there, the robot uses a three-layer control system to determine motion control, when it should hit the puck, defend its goal or stay still, and a third that determines how it should react to its opponent's playing style."

Comment Re:We Wish (Score 1) 663

If you think we'll make plastic gadgets out of hydrocarbons from Titan, you're wrong. No matter how much we improve space technology, it will always be insanely expensive compared to sucking oil out of a well, manufacturing a bit of plastic out of it, and loading it onto a ship for transport.


Submission Dennis Tito Proposes "A Mission for America": Two Humans to Mars

RocketAcademy writes: "Dennis Tito, the first citizen space explorer to visit the International Space Station, has created the Inspiration Mars Foundation to raise funds for an even more dramatic mission: a human flyby of the planet Mars.

Tito, a former JPL rocket scientist who later founded the investment firm Wilshire Associates, proposes to send two Americans — a man and a woman — on a 501-day roundtrip mission which would launch on January 5, 2018. Technical details of the mission can be found in a feasability analysis which Tito is scheduled to present at the IEEE Aerospace Conference in March.

Former NASA flight surgeon Dr. Jonathon Clark, who is developing innovative ways of dealing with radiation exposure during the mission, called the flight “an Apollo 8 moment for the next generation.""

Comment Re:Why not build spacecraft there? (Score 1) 186

You're called DirtyLiar, so probably a troll. I'll make this short.

Just off the top of my head, some of those technologies include:

Do you like computers, cell-phones, or palm-tops? Computers were a direct result of needing near instantaneous calculations using data that would be unknown until the moment it was going to be used. The invention of both the transistor, and the computer chip can be traced back to the need to make components as compact and light as possible. As was their subsequent miniaturization.

Computers were invented in WWII. Transistors were invented in 1947. Integrated circuits were invented in 1949, but not used on the Saturn V.

How about the convenience of microwave ovens,

Available since 1947.

or freeze dried food?

WWII tech. I'll stop now.

C++ is the best example of second-system effect since OS/360.