IOprestanda

IOprestanda (IO performance) is the measure of speed and responsiveness of input/output operations in a computer system. It commonly concerns storage devices, but can also involve memory and network storage. In practice, IO performance is described using latency, throughput, and IOPS.

Key metrics include IOPS, throughput (MB/s), and latency (ms). IOPS counts how many IO operations are completed per second; throughput measures data moved per second; latency is the time from issuing an IO to its completion. Workloads can be sequential or random, with different block sizes affecting results and cache effects.

Factors influencing IO performance include hardware (HDDs, SSDs, NVMe), interfaces (SATA, PCIe), and storage topology (RAID, JBOD). Software factors include file systems, OS I/O schedulers, drivers, virtualization, and caching. Networked storage adds latency via protocols such as iSCSI, NFS, or SMB.

Measurement and benchmarking use tools like fio, iostat, ioping, bonnie++, and hdparm. Benchmarks should reflect representative workloads and account for warm-up and caching; synthetic results may differ from real-world performance.

Optimization focuses on matching hardware and workload: databases benefit from low latency and high IOPS, while media servers emphasize sustained throughput. Tuning parameters such as block size, queue depth, and caching, as well as storage tiering or faster media, can improve IO performance.