NonIO

NonIO is a term used in computing to describe operations, components, or systems that do not involve input or output. It is commonly used to contrast CPU-bound or in-memory computation with I/O-bound tasks that depend on data transfer to storage, networks, or devices.

In software development, nonIO tasks operate on data that already resides in memory. Examples include numerical algorithms, data analysis in memory, cryptographic hashing of in-memory payloads, or simulations that read data from RAM rather than from disk or network. Such tasks typically emphasize processor speed, cache locality, and memory bandwidth rather than throughput of external devices.

In hardware and system design, non-IO elements refer to computational units such to CPU cores and memory subsystems that do not directly perform input/output. Memory hierarchies, caches, and arithmetic logic units are considered non-IO when measuring internal computation performance.

In benchmarking and performance engineering, nonIO isolates compute performance by minimizing or excluding disk and network activity. This helps compare algorithms and architectures based on processing capability rather than data transfer rates.

Limitations: the nonIO distinction is a simplification. Real workloads often alternate between computation and I/O, and asynchronous I/O can overlap these phases. The term is most useful as a descriptive aid rather than a strict metric.

See also: I/O, CPU-bound, memory-bound, asynchronous I/O, buffering.