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Linux

Submission + - Ext4 scare was a tempest in a teacup: almost all of the userbase safe (gmane.org)

Submitted by Anonymous Coward
An anonymous reader writes: It turns out the ext4 problem only affects users of some very obscure mount options, and even them it depends on specific conditions to show up. If you DON'T use the mount options "journal_async_commit" or "journal_checksum", which are NEVER enabled by default (not by the system, and not by the distros), you will not see any corruption.
AMD

Submission + - Did AMD Drop Support for Windows XP? (ngohq.com)

Submitted by Anonymous Coward
An anonymous reader writes: Yesterday, AMD released Catalyst 12.10 and Catalyst 12.11 Beta. It appears that both drivers don't support Windows XP. In fact, XP isn't even listed in the Catalyst 12.10 release notes.
AMD

Submission + - Vishera-based AMD FX processors make debut (techreport.com)

Submitted by
crookedvulture
crookedvulture writes: "The next generation of AMD FX processors has arrived. Otherwise known as Vishera, this new chip features up to eight cores based on the updated Piledriver microarchitecture. It's a speed demon, with clocks ranging as high as 4.2GHz in Turbo mode, and relatively inexpensive, with prices under $200. For heavily threaded tasks, the top-of-the-line FX-8350 offers largely better performance than competing Intel chips. However, the FX's performance isn't as impressive in single-threaded workloads and in games. The chip is also quite a power hog, pulling over 100W more at the wall socket than an equivalent Intel CPU. All of the FX chips have unlocked multipliers, though, and it looks like they might be decent overclockers."
Book Reviews

Submission + - Book Review: C++ Primer (Fifth Edition) (amazon.com)

Submitted by
asgard4
asgard4 writes: "Title: C++ Primer (Fifth Edition)
Authors: Stanley B. Lippman, JoséeLajoie, Barbara E. Moo
Publisher: Addison-Wesley
976 pages
ISBN-13: 978-0-321-71411-4
ISBN-10: 0-321-71411-3
Price: $59.99

The updated C++ language ISO standard released in September 2011 (called C++11 by most people instead of its full, glorious name ISO/IEC 14882:2011) extends C++ in a myriad of ways, both at a language and at a library level. Even though there aren’t any compilers that fully support all the new language extensions yet, C++ books are already getting updated to include the new features. Quite possibly one of the best books to learn C++ is the classic book C++ Primer by Lippman, Lajoie, and Moo, which received a significant facelift in its fifth edition to include most (but not all) new C++11 features.

Unlike other books that start with discussing the C subset of C++ and the more low-level, procedural features of the language, C++ Primer immediately introduces various higher-level features, such as classes and the use of the standard library types string and vector. I think this is a good choice, considering that the book is written for a target audience that is already familiar with programming, but just not in C++. The book is also a very good introduction to the new C++11 features for programmers that already have experience with the “old” C++98. To aid this subset of readers, the authors have kindly added little icons next to the text that discusses C++11.

After presenting a quick and simple example program, the book introduces how to define variables of different types and how to create compound data structures, followed by a brief look at the standard library string and vector classes. Almost all later examples in the book will use at least these basic types. This is followed by the usual tour through most of the different types of expressions and statements C++ offers.The book continues with a detailed discussion of functions, how they can be overloaded, how default arguments work, how the new C++11 constexpr functions work, and how argument types are converted when functions are called. The authors do a great job at covering almost all possible argument types, from passing C-style arrays as references, to functions that accept the new C++11 initializer lists or old-style ellipsis parameters. In general, I think this thoroughness is a good thing. At the same time, it shows the complexity of the language when it takes almost 60 pages to describe how functions are defined and called.The book concludes its first part with a basic look at classes and some hints to object-oriented programming in C++.

Part II of the book is a brief tour of parts of the C++ standard library, in particular IO streams, various sequential and associative containers (including the new C++ unordered containers) and finally dynamic memory and smart pointers. This part is almost an interlude before the book continues with more concepts with regards to classes in part III, in which the presented examples make use of the standard library facilities from part II. A whole chapter in part III is dedicated to copy control, quite an important and often not very well understood concept in C++. There is also ample discussion of the Rule of Three, which states that a class that requires a destructor also needs a copy constructor and an assignment operator. Of course, with the new C++11 rvalue references this becomes the Rule of Five, which requires that such a class should also have a move constructor and a move assignment operator. The discussion of rvalue references and moving objects in C++11 is excellent, in my opinion. Well worth the read, even for experienced C++98 developers.

The book continues with operator overloading and an in-depth look at polymorphism via virtual functions. The new C++11 keywords final and override are discussed, as well as virtual destructors and pure virtual functions. The final chapter in this part of the book is about templates. The discussion is quite detailed, with a good coverage of class templates, function templates, template specialization and the new variadic templates that were introduced with C++11. There is also ample treatment of how rvalue reference template parameters behave in template argument deduction — quite an interesting topic that has some surprising properties. When passing an lvalue reference to an rvalue reference template parameter, the deduced type is an lvalue reference because of how references get collapsed during argument deduction. C++ guru Scott Meyers recently called this type of rvalue reference a “universal reference” in talk he gave. (http://channel9.msdn.com/Shows/Going+Deep/Cpp-and-Beyond-2012-Scott-Meyers-Universal-References-in-Cpp11)

The final part of the book deals with a few more topics that didn’t fit anywhere else in the book.In particular, there is discussion of some more standard library classes (tuples, regular expressions, and random number generators), exception handling, namespaces, overloading the new and delete operators, and some other random topics. Overall, the book’s coverage of the language is pretty thorough, but there are some things that it doesn’t discuss or even bring up at all. For one thing, there is no mention of template metaprogramming. There is a short mention of the new C++11 type traits templates, which can be considered template metaprogramming to some degree, but that’s pretty much it. I think for a primer that’s alright.However, a short chapter that shows some basic metaprogramming with types might have been nice. Also, there is no mention of the new C++11 memory model, multi-threading, or thread-local storage.

Most of the changes introduced with C++11 are certainly useful in a lot of contexts and allow us to write more concise and modern C++ programs. However, I can’t shake the feeling that C++ — already an incredibly complex language to learn and even more difficult to master — has become so cluttered with features that it’s becoming a herculean task to teach the language. C++ Primer reinforces that feeling. While an excellent book at giving the reader a thorough introduction to the language, the book’s more than 900 densely information-packed pages confirm that learning C++11 takes a lot of dedication. Nevertheless, the book is a great guide along the journey, if the reader is willing to immerse herself in the intricacies of the C++ programming language. I highly recommend C++ Primer to any programmer interested in starting to learn the ropes of C++."

Submission + - The most detailed images of Uranus' atmosphere ever

Submitted by monkeyhybrid
monkeyhybrid writes: The Planetary Society's Emily Lakdawalla reports on the most detailed images of Uranus ever taken. The infrared sensitivity of the ground based Keck II telescope's NIRC2 instrument enabled astronomers to see below the high level methane based atmosphere that has hampered previous observations, and with unprecedented clarity. If you ever thought Uranus was a dull blue looking sphere then look again; you could easily mistake these images for being of Jupiter!
Cloud

Submission + - Amazon EBS failure brings down Reddit, Imgur, others (networkworld.com) 1

Submitted by
BButlerNWW
BButlerNWW writes: "Amazon Web Services has confirmed that its Elastic Block Storage (EBS) service is experiencing degraded service, leading sites across the Internet to experience downtime, including Reddit, Imgur and many others.

AWS confirmed on its status page at 2:11 p.m. ET that it is experiencing "degraded performance for a small number of EBS volumes." It says the issue is restricted to a single Availability Zone within the US-East-1 Region, which is in Northern Virginia. AWS later reported that its Relational Database Service (Amazon RDS) and its Elastic Beanstalk application plaform also experienced failures on Monday afternoon."
Earth

Submission + - A Trio of Oil Companies Now Fracking the Nile

Submitted by derekmead
derekmead writes: Some 97% of Egyptians get their drinking water from the Nile, a little north-flowing river in Africa that is also probably the most famous body of water in the world. Without the Nile, civilization in water-scarce, rainfall-allergic Egypt isn’t possible. No wonder, then, that some of the nation’s 90 million citizens are incensed by the growing number of oil and gas fracking operations popping up a little too close to its lifeblood.

At least three major companies — the Dutch oil giant Shell, the American oil and gas corporation Apache, and the United Arab Emirates-based Dana Gas — have launched major hydraulic fracturing operations in Egypt. Apache and Dana have been fracking directly in the Nile valley.

Dana just announced a brand new natural gas discovery yesterday: between 4 and 6 billion cubic feet lie below the Nile Delta, where it plans to frack. According to the Egypt Independent, Apache has a fracking operation “in the Western Desert near important aquifers.”

Shell is the latest to the game; it’s using a new waterless technique, foam fracking, to tap into gas reserves previously thought unreachable. In August, it began drilling 65 exploratory wells, and hopes to ramp natural gas production up from 0.5 million cubic feet a day to 5 million cf/d.
Google

Submission + - 17th century microscope book is now freely readable (downloadtheuniverse.com) 2

Submitted by menno_h
menno_h writes: In January 1665, Samuel Pepys wrote in his diary that he stayed up till two in the morning reading a best-selling page-turner, a work that he called "the most ingenious book I read in my life." It was not a rousing history of English battles or a proto-bodice ripper. It was filled with images: of fleas, of bark, of the edges of razors.

The book was called Micrographia. It provided the reading public with its first look at the world beyond the naked eye. Its author, Robert Hooke, belonged to a brilliant circle of natural philosophers who--among many other things--were the first in England to make serious use of microscopes as scientific instruments. They were great believers in looking at the natural world for themselves rather than relying on what ancient Greek scholars had claimed. Looking under a microscope at the thousands of facets on an insect's compound eye, they saw things at the nanoscale that Aristotle could not have dreamed of. A razor's edge became a mountain range. In the chambers of a piece of bark, Hooke saw the first evidence of cells.
Micrographia is is available on Google Books now.
Crime

Submission + - The Pirate Bay Founder's Jailing Sounds a Little Extreme (vice.com)

Submitted by
pigrabbitbear
pigrabbitbear writes: "Things aren’t looking awesome for Pirate Bay founder Gottfrid Svartholm, who’s currently under lock and key in a newly built jail about 15 minutes north of Stockholm. Svartholm’s mother Kristina says that her 28-year-old boy is being held in solitary confinement for 23 hours a day without any human contact other than his interactions with the guards. It’s been nearly two months since Svartholm was arrested in Cambodia, where he’d been living for years, and extradited back to Sweden, where he’s due to spend a year behind bars and pay a $1.1 million fine for copyright offenses related to his role at the Pirate Bay. But that’s not why Sweden’s being so tough on him in prison. Authorities believe he may have played a role in the hacking of Logica, a Swedish technology company with ties to the country’s tax authorities. They haven’t charged him with any crimes yet in that case, however."
Cloud

Submission + - NASA achieves data goals for Mars rover with open source software (opensource.com)

Submitted by
caseyb89
caseyb89 writes: "Open source projects Nginx, Railo CMS, and GlusterFS are powering Mars Curiosity's big data crunching. "Taken together, the combination of cloud and open source enabled the Curiosity mission to provide beautiful images in real time, not months delayed; at high quality, not "good enough" quality. A traditional, proprietary approach would not have been this successful, given the short time to deployment and shifting requirements that necessitated the ultimate in agility and flexibility.""
Moon

Submission + - A Supercomputer on the Moon to Direct Deep Space Traffic 1

Submitted by
Hugh Pickens writes
Hugh Pickens writes writes: "NASA currently controls its deep space missions through a network of 13 giant antennas in California, Spain and Australia known as the Deep Space Network (DSN) but the network is obsolete and just not up to the job of transmitting the growing workload of extra-terrestrial data from deep space missions. That's why Ouliang Chang has proposed building a massive supercomputer in a deep dark crater on the side of the moon facing away from Earth and all of its electromagnetic chatter. Nuclear-powered, it would accept signals from space, store them, process them if needed and then relay the data back to Earth as time and bandwidth allows. The supercomputer would run in frigid regions near one of the moon’s poles where cold temperatures would make cooling the supercomputer easier, and would communicate with spaceships and earth using a system of inflatable, steerable antennas that would hang suspended over moon craters, giving the Deep Space Network a second focal point away from earth. As well as boosting humanity's space-borne communication abilities, Chang's presentation at a space conference (PDF) in Pasadena, California also suggests that the moon-based dishes could work in unison with those on Earth to perform very-long-baseline interferometry, which allows multiple telescopes to be combined to emulate one huge telescope. Best of all the project has the potential to excite the imagination of future spacegoers and get men back on the moon."

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