| Borislav Petkov | 9b45ef4 | 2015-08-12 18:29:42 +0200 | [diff] [blame^] | 1 | menuconfig RAS |
| 2 | bool "Reliability, Availability and Serviceability (RAS) features" |
| 3 | help |
| 4 | Reliability, availability and serviceability (RAS) is a computer |
| 5 | hardware engineering term. Computers designed with higher levels |
| 6 | of RAS have a multitude of features that protect data integrity |
| 7 | and help them stay available for long periods of time without |
| 8 | failure. |
| 9 | |
| 10 | Reliability can be defined as the probability that the system will |
| 11 | produce correct outputs up to some given time. Reliability is |
| 12 | enhanced by features that help to avoid, detect and repair hardware |
| 13 | faults. |
| 14 | |
| 15 | Availability is the probability a system is operational at a given |
| 16 | time, i.e. the amount of time a device is actually operating as the |
| 17 | percentage of total time it should be operating. |
| 18 | |
| 19 | Serviceability or maintainability is the simplicity and speed with |
| 20 | which a system can be repaired or maintained; if the time to repair |
| 21 | a failed system increases, then availability will decrease. |
| 22 | |
| 23 | Note that Reliability and Availability are distinct concepts: |
| 24 | Reliability is a measure of the ability of a system to function |
| 25 | correctly, including avoiding data corruption, whereas Availability |
| 26 | measures how often it is available for use, even though it may not |
| 27 | be functioning correctly. For example, a server may run forever and |
| 28 | so have ideal availability, but may be unreliable, with frequent |
| 29 | data corruption. |
| 30 | |
| 31 | if RAS |
| 32 | endif |