The VAX Unit of Performance, commonly known as VUP, was once a significant measure in the world of computing. Developed by Digital Equipment Corporation (DEC), this metric was used to gauge the performance of computer systems, particularly those in the VAX series. Although now considered obsolete, the VUP played a crucial role in the evolution of computer performance metrics.
The Origin of VUP
The VAX Unit of Performance was introduced by DEC as a way to quantify the
performance of their VAX computer systems. Specifically, 1 VUP was defined as the performance level of a VAX 11/780 completing a given task. This standardization allowed for a consistent benchmark across different VAX models, making it easier for users to compare the capabilities of various systems.
The VAX 11/780 was a popular model in the VAX series, and its performance became the baseline for the VUP measurement. This approach was particularly useful in an era when computing power was rapidly advancing, and users needed a reliable way to assess the capabilities of new machines. By using the VUP, DEC provided a straightforward method for customers to understand the relative performance of their products.
VUP in Practice
In practice, the VUP was used to compare the performance of different VAX machines and later workstation designs. For example, a system running at 3.8 VUPs would be approximately 3.8 times faster than the VAX 11/780. This metric was particularly useful for organizations that relied on VAX systems for their computing needs, as it allowed them to make informed decisions about upgrades and new purchases.
The VUP was roughly equivalent to 1 MIPS (Million Instructions Per Second), another common performance metric at the time. This equivalence meant that the VUP could often be used interchangeably with MIPS, providing additional flexibility for users comparing systems from different manufacturers.
The Decline of VUP
Despite its initial popularity, the VUP eventually fell out of favor as more standardized performance ratings, such as SPEC, became widely adopted. The introduction of DEC workstations running Unix further diminished the relevance of the VUP, as it was less useful for comparing these platforms to competing systems.
As the computing industry evolved, the need for more comprehensive and universally applicable performance metrics became apparent. The VUP, while useful in its time, was ultimately limited by its focus on a specific set of DEC products. Today, it serves as a reminder of the early days of computer performance measurement and the ongoing quest for more accurate and meaningful benchmarks.
