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series of temporary files. Then merge all the sorted temporary files into one big sorted file.

If your data consists of integers only, and they are all in a fairly narrow range, try the bucket sort in demo\allsorts.e.

Taking Advantage of Cache Memory

As CPU speeds increase, the gap between the speed of the on-chip cache memory and the speed of the main memory or DRAM (dynamic random access memory) becomes ever greater. You might have 256 Mb of DRAM on your computer, but the on-chip cache is likely to be only 8K (data) plus 8K (instructions) on a Pentium, or 16K (data) plus 16K (instructions) on a Pentium with MMX or a Pentium II/III. Most machines will also have a "level-2" cache of 256K or 512K.

An algorithm that steps through a long sequence of a couple of thousand elements or more, many times, from beginning to end, performing one small operation on each element, will not make good use of the on-chip data cache. It might be better to go through once, applying several operations to each element, before moving on to the next element. The same argument holds when your program starts swapping, and the least-recently-used data is moved out to disk.

These cache effects aren't as noticeable in Euphoria as they are in lower-level compiled languages, but they are measurable.

Using Machine Code and C

Euphoria lets you call routines written in machine code. You can call C routines in dynamically loaded library files, and these C routines can call your Euphoria routines. You might need to call C or machine code because of something that can not be done directly in Euphoria, or you might do it for improved speed.

To boost speed, the machine code or C routine needs to do a significant amount of work on each call, otherwise the overhead of setting up the arguments and making the call will dominate the time, and it might not gain you much.

Many programs have some inner core operation that consumes most of the CPU time. If you can code this in C or machine code, while leaving the bulk of the program in Euphoria, you might achieve a speed comparable to C, without sacrificing Euphoria's safety and flexibility.

Using The Euphoria To C Translator

The Euphoria To C Translator is included in the installation package. It will translate any Euphoria program into a set of C source files that you can compile using a C compiler.

The executable file that you get using the Translator should run the same, but faster than when you use the interpreter. The speed-up can be anywhere from a few percent to a factor of 5 or more.