ISO/IEC 30134-5:2017

Overview

ISO/IEC 30134-5:2017 defines IT Equipment Utilization for servers (ITEUsv) as a Key Performance Indicator (KPI) to quantify average server utilization in a data centre. The standard specifies a conceptual definition, measurement approach, reporting rules and practical guidance to use CPU utilization as a proxy for server activity. ITEUsv is intended to help data centre owners/operators improve the aggregate energy efficiency of servers through consolidation, virtualization and operational changes.

Key topics and technical requirements

• Definition: ITEUsv is the average CPU utilization ratio of all servers (or a designated group) in a data centre.
• Per‑time formula: At time t, ITEUsv(t) = (Σ CUSi(t)) / N, where CUSi(t) is CPU utilization for server i and N is the number of running servers.
• Annual measurement: Monitor ITEUsv(t) continuously for one year and compute the annual average ITEUsv. Measurement intervals (e) must be between 1 minute and 1 hour; choose interval based on workload dynamics.
• Multicore/CPU handling: For multicore systems, CUSi(t) is the average utilization across cores; for multiple CPUs, the average across CPUs.
• Exclusions:
  • Servers where most computation is done by auxiliary processing accelerators (APAs) are out of scope.
  • Servers without applicable CPU monitoring tools should be excluded from the measurement group.
  • Servers in “power OFF” state are subtracted when calculating ITEUsv.
• Reporting: Record annual average, peak ITEUsv(t) and peak duration metrics to support target-setting and operational planning.
• Limitations: ITEUsv relies on CPU utilization as a proxy - consider memory, I/O, workload changes and differing OS/CPU measurement semantics when interpreting results.

Practical applications and users

• Who uses it: data centre operators, hosting/cloud providers, sustainability and capacity planners, IT operations and performance engineers.
• Use cases:
  • Track and improve server energy effectiveness by increasing average utilization (via virtualization, consolidation, workload scheduling).
  • Validate the impact of operational changes (server provisioning, autoscaling policies, power management).
  • Set internal targets (annual average and acceptable peak durations) and monitor trends year-over-year.
• Operational guidance:
  • Choose an appropriate sampling interval (1 min–1 h) reflecting workload variability.
  • Monitor continuously for a year for representative results.
  • Use peak and duration data to avoid unacceptable performance impact when raising average utilization.

Related standards

• ISO/IEC 30134-1 - Overview and general requirements for data centre KPIs.
• ISO/IEC 30134-2 - PUE (Power Usage Effectiveness) for infrastructure energy efficiency.
• ISO/IEC 30134-4 - Addresses capability/capacity aspects complementary to utilization.

Keywords: ISO/IEC 30134-5:2017, ITEUsv, data centre KPI, server utilization, CPU utilization, energy efficiency, PUE, server consolidation.