Compute centers have passed through several major evolutions during the past 30 years. From the storage systems perspective, the evolution has fundamentally changed the way data is structured, represented, stored and accessed, moving from supercomputer attached file systems to massively distributed services. Throughout this period, new hardware technologies, whether for computing or for data storage, have in turn brought major changes, even broken new ground, and posed real scientific challenges. To address these challenges, innovative concepts and paradigms have been introduced with various implementations and integrated into large-scale solutions which remain in continuous evolution, reconciling hardware advances, application requirements, and contextual constraints. This article retraces the milestones of this technological journey in a chronological order, starting with the Petascale period and the introduction of IO-Proxies to meet the need for increasing storage capacity and reduced access latency, exploring a wealth of data structures, protocols, and other software components to build parallel, efficient and scalable solutions. The challenges of the Exascale era were even greater and innovations were introduced to address them, especially in terms of scheduling policies to match the complexity of the associated workflows and dataflows. Then, the IO-Proxies evolved to a more versatile paradigm implementing the Ephemeral Services.
Deniel et al. (2026) studied this question.