Events Archive: Fall 2002

Perl, the Practical Extraction and Reporting Language can only be described as an eclectic language, invented and refined by a deranged system administrator, who was trained as a linguist. This man, however, has declared:

• Perl 5 was my rewrite of Perl. I want Perl 6 to be the community's rewrite of Perl and of the community. *

--- Larry Wall

Whenever a language is designed by a committee, it is common wisdom to avoid it. Not so with Perl, for it cannot get worse. However strange these Perl people seem, Perl 6 is a good thing coming. In this talk, I will demonstrate some Perl 5 programs, and talk about their Perl 6 counterparts, to show you that Perl 6 will be cleaner, friendlier, and prettier.

Modern graphics accelerators, or "GPUs", have embedded high-performance programmable components in the form of vertex and fragment shading units. Recently, these units have evolved from 8-bit computations to floating-point, and other operations provide array gather, scatter, and summation. These capabilities make GPUs akin to array processors of the past, but with a difference: every PC now has one! I am interested in finding the best way to exploit this computational capacity for not only graphics but for general-purpose computation.

Current APIs permit specification of the programs for GPUs using an assembly-language level interface. Compilers for high-level shading languages are available, such as NVIDIA's Cg, and OpenGL 2.0 and DirectX will also include standardized shading languages. This talk will review these. However, compilers for these languages read in an external string specification, which can be inconvenient.

However, it is possible, using standard C++, to define a high-level shading language directly in the API. Such a language can be nearly indistinguishable from a special-purpose programming language, yet permits more direct interaction with the specification of textures (arrays) and parameters, simplifies implementation, and enables on-the-fly generation, manipulation, and specialization of shader programs. A shading language built into the API also permits the lifting of C++ host language type, modularity, and scoping constructs into the shading language without any additional implementation effort. Such an embedded language could be used to program other embedded processors (such as DSP chips in sound cards) or even to generate machine language on the fly for the host CPU.

Do you ever wonder what java is doing while you wait? Have you ever used Modula-3? Do you wonder how lazily you can Mark and Sweep? Would you like to know how to Stop-and-Copy?

Come out to this talk and learn these things and more. No prior knowledge of Garbage Collection or memory management is needed.

Templates are a useful feature in C++ when it comes to writing type-independent data structures and algorithms. Relatively soon after their appearance it was realised that they could be used to do much more than this. Essentially it is possible to write certain programs in C++ that execute completely at compile time rather than run time. Combined with constant-expression optimisation this is an interesting twist on regular C++ programming.

This talk will give a short overview of the features of templates and then go on to describe how to "abuse" templates to perform complex computations at compile time. The speaker will present three programs of increasing complexity which execute at compile time. First a factorial listing program, then a prime listing program will be presented. Finally the talk will conclude with the presentation of a Mandelbrot generator running at compile time.

If you are interested in programming for the fun of it, the C++ language or silly tricks to do with languages, this talk is for you. No C++ knowledge should be necessary to enjoy this talk, but programming experience will make it more worthwile for you.

Virtual memory management is one of the cornerstones of multiuser operating systems. Most systems available today place all of the policy in a monolithic virtual memory manager, VMM, isolated from the rest of the system. Although secure and lightweight, users have no way to communicate their anticipated memory needs and usage to the system pager. As a result, the VMM can only implement a global paging policy (typically, an approximation of LRU) which may be good on average but is best for nobody.

With the port of Hurd to the L4 microkernel, this situation is being readdressed. Due to its more distributed nature, a centralized resource manager is not only more difficult to implement efficiently but also contrary to the philosophy of the rest of the system. We are currently exploring a model whereby each program is fully self-paged and all compete for memory from a physical memory server. This talk will first discuss how paging currently works in Mach and other systems. An argument for an external paging policy will then be presented followed by the requirements of such a design and the design itself.

Neal Walfield, a GNU Hurd developer, is from the University of Massachusetts Lowell. Neal spent the summer of 2002 at University of Karlsruhe working on porting the GNU Hurd to L4.

This whirlwind talk is aimed at providing an overview of the GNU/Linux port for the HP PARISC processor. The talk will focus on the "intricacies" of the processor, and in particular the implementations of the Linux kernel and GNU Libc. After the talk you should be acutely aware of how little code needs to be written to support a new architecture! Carlos has been working on the port for two years, and enjoying the fruits of his labour on a 46-node PARISC cluster.

Carlos is currently in his 5th year of study at the University of Western Ontario. This is his last year in a concurrent Computer Engineering and Computer Science degree. His research interest range from distributed and parallel systems to low level optimized hardware design. He likes playing guitar and just bought a Cort NTL-20, jumbo body, solid spruce top with a mahogany back. Carlos hacks on the PARISC Linux kernel, GNU libc, GNU Debugger, GNU Binutils and various Debian packages.

No abstract available yet.

This is the second in a series of seminars that cover the use of the UNIX Operating System. UNIX is used in a variety of applications, both in academia and industry. We will provide you with hands-on experience with the Math Faculty's UNIX environment in this tutorial.

Topics that will be discussed include:

• Interacting with Bourne and C shells
• Editing text using the vi text editor
• Editing text using the Emacs display editor
• Multi-tasking and the screen multiplexer

If you do not have a Math computer account, don't panic; one will be lent to you for the duration of this class.

The executive has unanimously decided to try to change our constitution to comply with MathSoc policy. The clause we are trying to change is the membership clause. The following is the proposed new reading of the clause.

• In compliance with MathSoc regulations and in recognition of the club being primarily targeted at undergraduate students, full membership is open to all undergraduate students in the Faculty of Mathematics and restricted to the same.*

The proposed change is illustrated on a web page.

There will be a business meeting on 30 Sept 2002 at 18:30 in the comfy lounge, MC 3001. Please come and vote

Vote for the exec this term. Meet at the comfy lounge. There will be an opportunity to obtain or renew memberships. This term's CRO is Siyan Li (s8li@csclub.uwaterloo.ca).