# XP/S4
**Wikidata**: [Q69816860](https://www.wikidata.org/wiki/Q69816860)  
**Source**: https://4ort.xyz/entity/xp-s4-q69816860

## Summary
XP/S4 is a supercomputer manufactured by Intel, designed to run on the OSF/1 operating system. It features 56 processor cores and achieved a peak performance of 2.8 gigaflops in 1994. As a notable entry in the Top500 list, it contributed to advancements in high-performance computing during the 1990s.

## Key Facts
- **Instance of**: Supercomputer.
- **Manufacturer**: Intel.
- **Operating System**: OSF/1 (a Unix variant developed by the Open Software Foundation).
- **Top500 System ID**: 859.
- **Performance (1994)**: Rmax of 1.75 gigaflops (June and November 1994); Rpeak of 2.8 gigaflops.
- **Processor Cores**: 56.
- **Related Operating System**: Tru64 UNIX (inception: 1992, developed in the United States).

## FAQs
### Q: Who manufactured the XP/S4 supercomputer?
A: The XP/S4 was manufactured by Intel, a leading American multinational technology company.

### Q: What operating system did XP/S4 use?
A: XP/S4 ran on OSF/1, a Unix-based operating system developed by the Open Software Foundation.

### Q: How powerful was the XP/S4 in terms of performance?
A: In 1994, the XP/S4 achieved a maximum performance (Rmax) of 1.75 gigaflops and a peak performance (Rpeak) of 2.8 gigaflops.

## Why It Matters
XP/S4 holds significance as a representative of 1990s supercomputing innovation, leveraging Intel’s hardware and the OSF/1 operating system to deliver high-performance capabilities. Its inclusion in the Top500 list underscored its role in scientific and technical computing, reflecting the rapid evolution of processing power during this period. As a 56-core system, it exemplified the push for multi-processor architectures to solve complex computational challenges, influencing the trajectory of high-performance computing (HPC) development.

## Notable For
- **Multi-Core Architecture**: Featured 56 processor cores, a notable design for its time.
- **Top500 Recognition**: Earned a spot in the Top500 list of the world’s fastest supercomputers (ID: 859).
- **Unix-Based Performance**: Demonstrated the viability of OSF/1 in high-performance environments.
- **Intel Innovation**: Showcased Intel’s contributions to supercomputing during the 1990s.

## Body
### Operating System
XP/S4 relied on **OSF/1**, a Unix variant developed by the Open Software Foundation. This operating system was distinct from Tru64 UNIX, another Unix-based OS developed in the United States since 1992.

### Hardware Specifications
- **Manufacturer**: Intel, a semiconductor industry leader founded in 1968.
- **Processor Cores**: The system utilized 56 processor cores, a significant configuration for 1990s supercomputing.

### Performance Benchmarks
- **1994 Metrics**:
  - **Rmax (Sustained Performance)**: 1.75 gigaflops (recorded June 1 and November 1, 1994).
  - **Rpeak (Theoretical Peak)**: 2.8 gigaflops (recorded June 1 and November 1, 1994).

### Historical Context
As part of the Top500 list, XP/S4 reflected the competitive landscape of supercomputing in the 1990s. Its Intel architecture and Unix-based software stack positioned it as a tool for academic and industrial research, contributing to fields requiring intensive computational resources.