Definition

ExaScale Index (ESI)

A framework for describing progress toward exascale compute capability using transparent dimensions such as performance, efficiency, scalability, and reliability.

The ExaScale Index (ESI) is a structured way to summarize how close a computing system, platform, or ecosystem is to achieving exascale capability—commonly understood as order-of-magnitude compute at or exceeding 1018 operations per second.

Rather than treating exascale as a single threshold, ESI expresses readiness across multiple dimensions that must advance together for exascale capability to be practical, repeatable, and sustainable.

Purpose

Core Dimensions

1) Compute Throughput

Operations per second under defined workload and precision.

2) Energy Efficiency

Performance per watt including infrastructure overhead.

3) Scalability & Interconnect

Growth efficiency as nodes are added.

4) Memory & Data Movement

Ability to feed compute with sufficient data bandwidth.

5) Reliability & Fault Tolerance

Error handling and recovery at extreme scale.

6) Practical Deployability

Cost, manageability, and repeatability.

Scope Notes