Happy New Year! Check out some of the top blog posts from 2015:
Why Do Better Forecasts Matter?
Meteorologists have been striving to increase the accuracy of their work since the first weather forecasts were issued in the mid-19th century by pioneers such as Robert FitzRoy. In the 1950s and 1960s, the development of computers and observational technologies enabled forecast generation using the numerical weather prediction theories of Vilhelm Bjerknes and Lewis Fry Richardson. Today the numerical models that support our weather and climate forecasts are true “grand challenge” problems, requiring on the order of 10,000 billion (1016) mathematical operations and the exchange of 150 billion (1.5 x 1014) bytes of information to generate a contemporary global 10-day high-resolution forecast.
Algorithmic Trading: Faster Execution or Smarter Strategies?
The short answer is: You need both. Since the advent of the first high-frequency trading (HFT) firm, the quest for low-latency trading has been paramount. Strategies that were profitable before HFT are now obsolete. Among those strategies with questionable profitability today are:
- Arbitrage:Markets move too quickly to allow time for arbitrage.
- Market making:HFT imposes excessive risks on those traders.
- Event trading:Competing against HFT in terms of speed of response to scheduled economic reports and conventional news is impossible, since HFT systems can process and react to the information quicker.
High Performance Computing — the Last Rewrite
For the past 20 years, high performance computing has benefited from a significant reduction in the clock cycle of the basic processor. Going forward, trends indicate that the clock rate of the most powerful processors in the world may stay the same or decrease slightly. At the same time the amount of physical space that a computing core occupies is still trending downward. This means more processing cores can be contained within the chip.
Six Ways to Say “Hello” in Chapel
When learning a new programming language, users often start by studying “Hello world” programs —those that output simple messages to the console. Though such programs are trivial by nature, they can be an illuminating way to get familiar with a new language in a short amount of time.
In this series of articles, Brad Chamberlain shows several “Hello world” programs in Chapel, Cray’s open-source programming language for productive parallel programming. He starts with a pair of traditional (serial) “Hello world” programs and then moves on to parallel versions that take advantage of Chapel’s features for shared- and distributed-memory execution.
HPC Software Optimization Trends: Where Did We Come From and Where Are We Now?
To describe the current trajectory of software optimization trends in HPC, we need to understand our recent past. Which recent trends dictate our current state? We also need to know where we are now. Which HPC software optimizations are currently commonplace? Finally, to what extent does the trajectory created by past and current HPC software optimization activities predict the future? In this series, Cray HPC Software Engineer Aaron Vose discusses key findings of trends that have and will continue to impact the future of HPC software including:
- Rise of OpenMP and OpenACC
- More threads
- Wider vectors
- More complex memory hierarchies