162306a36Sopenharmony_ci# SPDX-License-Identifier: GPL-2.0-only 262306a36Sopenharmony_cimenuconfig RAS 362306a36Sopenharmony_ci bool "Reliability, Availability and Serviceability (RAS) features" 462306a36Sopenharmony_ci help 562306a36Sopenharmony_ci Reliability, availability and serviceability (RAS) is a computer 662306a36Sopenharmony_ci hardware engineering term. Computers designed with higher levels 762306a36Sopenharmony_ci of RAS have a multitude of features that protect data integrity 862306a36Sopenharmony_ci and help them stay available for long periods of time without 962306a36Sopenharmony_ci failure. 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_ci Reliability can be defined as the probability that the system will 1262306a36Sopenharmony_ci produce correct outputs up to some given time. Reliability is 1362306a36Sopenharmony_ci enhanced by features that help to avoid, detect and repair hardware 1462306a36Sopenharmony_ci faults. 1562306a36Sopenharmony_ci 1662306a36Sopenharmony_ci Availability is the probability a system is operational at a given 1762306a36Sopenharmony_ci time, i.e. the amount of time a device is actually operating as the 1862306a36Sopenharmony_ci percentage of total time it should be operating. 1962306a36Sopenharmony_ci 2062306a36Sopenharmony_ci Serviceability or maintainability is the simplicity and speed with 2162306a36Sopenharmony_ci which a system can be repaired or maintained; if the time to repair 2262306a36Sopenharmony_ci a failed system increases, then availability will decrease. 2362306a36Sopenharmony_ci 2462306a36Sopenharmony_ci Note that Reliability and Availability are distinct concepts: 2562306a36Sopenharmony_ci Reliability is a measure of the ability of a system to function 2662306a36Sopenharmony_ci correctly, including avoiding data corruption, whereas Availability 2762306a36Sopenharmony_ci measures how often it is available for use, even though it may not 2862306a36Sopenharmony_ci be functioning correctly. For example, a server may run forever and 2962306a36Sopenharmony_ci so have ideal availability, but may be unreliable, with frequent 3062306a36Sopenharmony_ci data corruption. 3162306a36Sopenharmony_ci 3262306a36Sopenharmony_ciif RAS 3362306a36Sopenharmony_ci 3462306a36Sopenharmony_cisource "arch/x86/ras/Kconfig" 3562306a36Sopenharmony_ci 3662306a36Sopenharmony_ciendif 37