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Learn to efficiently initialize memory on Power Architecture systems. Software Developer Carlos Cavanna compares simple loops clearing one bit at a time to more elaborate algorithms, including the dcbz instruction to zero whole cache lines at a time. The article concludes with some rough performance numbers to help you tune your own applications.

SELinux, the U.S. National Security Agency's implementation of mandatory access control, is the most prominent new security subsystem in Linux. It comes installed by default in Fedora and Red Hat Enterprise Linux and is available in easy-to-install packages in other distributions. This article shows you how to convert a non-SELinux system by hand in order to expose details about how SELinux is integrated into a system.

BogoSec is a source code metric tool that wraps multiple source code scanners, invokes them on its target code, and produces a final score that approximates the security quality of the code. This article discusses the BogoSec methodology and implementation, and illustrates the output of BogoSec when run on a number of test cases, including Apache Web server, OpenSSH, Sendmail, Perl, and others.

Make substantial improvements in performance analysis with a CPI analysis model built on the tools introduced in Part 1. Learn ways to analyze the specific performance counter data produced by profiling runs to obtain statistics for events which the CPU cannot directly report on.

As computers and consumer electronics devices become more connected, platform security becomes increasingly important for everyone from consumers to businesses. For consumers, privacy of data such as credit card numbers and social security numbers have always been of concern, but now new technologies such as voice-over-IP and personal video blogs bring new privacy concerns. The unrelenting evolution toward an even more open and connected computing infrastructure requires robust security to thrive. Learn how the Cell Broadband Engine processor's security architecture is uniquely suited for the challenges of this digital future.

This article describes the SPU pipeline configuration, performance metric, and trace facilities that are available in the IBM Full-System Simulator for the Cell BE platform. Find out the exact cycle where the SPE stalls, or identify a poor choice of branch predictions, using pipeline tracing in the Cell BE simulator.

Linux was one of the first cross-platform operating systems to use 64-bit processors, and now 64-bit systems are becoming commonplace in servers and desktops. Many developers are now facing the need to port applications from 32-bit to 64-bit environments. With the introduction of Intel Itanium and other 64-bit processors, making software 64-bit-ready has become increasingly important.

Be ‘nice’ to your computers and examine some general guidelines for tuning server performance. A computer is like an employee who does tasks for you -- it's a good idea to keep from overburdening them. Keep this from happening by using the UNIX ‘nice’ command.

By the end of this tutorial, you will know guide a system through booting, set kernel parameters, and shut down or reboot a system. The tutorial is organized according to the specific objectives of the LPI exam for this topic. If you're studying for certification -- or simply building a solid foundation in Linux systems administration -- you will be ready to proceed to the next tutorial in the exam 102 series.

This article begins a short series on workload performance analysis on Power Architecture systems. Part 1 introduces the CPU feature set and a variety of useful tools for collecting data. Cycles per instruction (CPI) is the measurement for analyzing the performance of a workload.

Improving the performance of your applications is rarely a wasted effort, but it's not always clear which functions the program is spending most of its execution time on. Learn how to pinpoint performance bottlenecks using gprof for both user-space and system calls on Linux.

Need a teeny-tiny, business-card-sized, open source operating system that squeezes a lot of software into a little space? Take a look at DSL Linux. This quick review shows you how to use the miniscule OS, highlights the on-board applications, details how to load and start it, and explains how to save between sessions when using a bootable CD.

The Thirty Years' War was long and dreary and mostly pointless, but in the end, some good came out of it: the Peace of Westphalia. The UNIX wars were also long, dreary, and mostly pointless, but much good came out of them too. As compared with other operating system standards -- which are often highly volatile at best or non-existent at worst -- when it comes to UNIX, the elements are so mixed in the documentation that Nature might stand up and say to all the world 'This is a standard.'

Google Maps API along with DB2, PHP, JavaScript, and XML let you create an easy-to-use map with your data on it. Pan to your zip code to see area-specific data. Use custom icons, change the map type, create a sidebar, and use event handlers. The author and his 9th grader son walk you through the process.

Enterprise metaprogramming is becoming more common all the time as graphical and textual utilities make programming tasks easier and more descriptive, all because of the continuing formalization process occurring under the Object Management Group's Model Driven Architecture (MDA). This article explores the limits of metaprogramming, describes MDA and the problems it can solve, and presents a short example of a textual system that uses MDA.

Researchers at the IBM Almaden Research Center have achieved high-quality line patterns using deep-ultraviolet 193nm optical lithography for spaced ridges 29.9nm wide, besting the 32nm industry-consensus, theoretical (until now) limit by 2.1nm (slightly wider than the diameter of a DNA helix). Dr. Allen postulates that this "high-index immersion" variant of DUV lithography might purchase about seven years of breathing room before the industry has to rewrite Moore's Law.

With Filesystem in Userspace (FUSE), you can develop a user space filesystem framework without understanding filesystem internals or learning kernel module programming. Follow this simple, step-by-step guide to install, customize, and enable FUSE and AFS, so you can create your own fully functional filesystem in user space in Linux.