###### Question 16772 – NTA-UGC-NET 2021 Dec & 2022 June Paper-2
November 18, 2023
###### Question 9899 – Computer-Organization
November 18, 2023
###### Question 16772 – NTA-UGC-NET 2021 Dec & 2022 June Paper-2
November 18, 2023
###### Question 9899 – Computer-Organization
November 18, 2023

A software system crashed 20 times in the year 2017 and for each crash, it took 2 minutes to restart. Approximately, what was the software availability in that year ?

Question 95 Explanation:
Software availability:
It is a software used to ensure that systems are running and available most of the time. High availability is a high percentage of time that the system is functioning. It can be formally defined as (1 – (down time/ total time))*100%. Although the minimum required availability varies by task, systems typically attempt to achieve 99.999% (5-nines) availability. This characteristic is weaker than fault tolerance, which typically seeks to provide 100% availability, albeit with significant price and performance penalties.
Given data,
– Software crashed 20 times in the year 2017
– Each crash = 2 minutes to restart
– Software availability = ?
1 year = 365 days = 365 * 1440 minutes = 525600 minutes
→ Crash time = 20 * 2

= 40 minutes

→ Software availability = (525600 – 40) / 525600

= 0.999924
= (0.999924 * 100)
= 99.9924 %

96.9924%
97.9924%
98.9924%
99.9924%