Linux and the Alpha

Part 2 brings us optimization techniques for speeding up code to get the best performance from your Alpha or other RISC processor.

The Alpha architecture is designed for performance and its implementations do indeed make for very fast systems. Since its chips run at very high clock frequencies, the Alpha usually benefits the most from simple techniques that improve the memory-system behavior of a given program or algorithm. A few of these techniques have been demonstrated in this article and shown to achieve performance improvements anywhere in the range of 10% to 1700%. Fortunately, the same techniques also seem to benefit the other CPU architectures. This is good news since it means that usually one optimized implementation will perform well across a broad range of CPUs.

The biggest hurdle to developing high-performance applications under Linux is the current lack of sophisticated performance analysis tools. The relative lack of such tools is not surprising; while most commercial Unix vendors have tools for their own architecture, few, if any, are multi-platform. To some degree this is inherent in the problem, but there is no question it would not be very difficult to create even better portable performance-analysis tools.

Linux is what makes low-cost Alpha-based Unix workstations a reality. While Digital UNIX currently comes with better compilers, runtime libraries and more tools for the Alpha, the price difference is such that one can easily make up for the performance difference by spending a little more money on a faster machine. Also, development of gcc and better libraries doesn't stand still. However, since most work is done on a voluntary basis, it does take some time. Even so, Linux is already a highly competitive platform for integer-intensive applications. For floating-point intensive and especially FORTRAN applications, things are not yet so mature. Fortunately, if one cannot afford to wait for a better compiler, there is always the option of purchasing one of the commercial FORTRAN compilers available for Linux/Alpha.


The author would like to thank Richard Henderson of Texas A&M University and Erik Troan of Red Hat Software for reviewing this paper on short notice. Their feedback greatly improved its quality. Errors and omissions are the sole responsibility of the author. This article was first given as a speech at Linux Expo 97 on April 5.


David is a graduate student in the Ph.D. program of the Computer Science department at the University of Arizona. He plans on graduating in August 1997 and to finally get a “Real Job”. He was involved in the Linux/Alpha port and has been sticking around in the free software community ever since. When not playing with computers, he enjoys the outdoors with his lovely wife. He can be reached via e-mail at


White Paper
Linux Management with Red Hat Satellite: Measuring Business Impact and ROI

Linux has become a key foundation for supporting today's rapidly growing IT environments. Linux is being used to deploy business applications and databases, trading on its reputation as a low-cost operating environment. For many IT organizations, Linux is a mainstay for deploying Web servers and has evolved from handling basic file, print, and utility workloads to running mission-critical applications and databases, physically, virtually, and in the cloud. As Linux grows in importance in terms of value to the business, managing Linux environments to high standards of service quality — availability, security, and performance — becomes an essential requirement for business success.

Learn More

Sponsored by Red Hat

White Paper
Private PaaS for the Agile Enterprise

If you already use virtualized infrastructure, you are well on your way to leveraging the power of the cloud. Virtualization offers the promise of limitless resources, but how do you manage that scalability when your DevOps team doesn’t scale? In today’s hypercompetitive markets, fast results can make a difference between leading the pack vs. obsolescence. Organizations need more benefits from cloud computing than just raw resources. They need agility, flexibility, convenience, ROI, and control.

Stackato private Platform-as-a-Service technology from ActiveState extends your private cloud infrastructure by creating a private PaaS to provide on-demand availability, flexibility, control, and ultimately, faster time-to-market for your enterprise.

Learn More

Sponsored by ActiveState