By rewriting their software with the instructions in mind, software developers will be able to improve application performance. In addition, the Pentium 4 will contain a 20-stage pipeline. The pipeline is a processor's assembly line. While this means the Pentium 4 will have a line twice the length of the 10-stage Pentium III, the longer pipeline will create room for speeding up the chip. The length of the pipeline has created a debate among analysts concerning how the chip will perform.
Longer pipelines allow processor designers to ratchet up the processor's speed.
If an instruction gets misplaced at stage 18, the chip has to return to stage one. The trace cache will ameliorate many of these problems and lead to an overall improvement in speed, said Gwennap. Glaskowsky agreed but cautioned that the benefit may not be as big as Intel might want customers to believe. Whether Intel can manufacture the chip in volume will also be a major question at the conference and beyond, as the company has struggled to produce 1-GHz Pentium IIIs in significant volume. Yu said the Pentium 4 will be in volume production toward the end of the year.