Question

The IT department of a bank provide customers access to the currency conversion rate table between 9:00 a.m. and 5:00 p.m. from Monday through Friday. It updates the table every day at 8:00 a.m. with a feed from the mainframe system. The update process takes 50 minutes to complete. On Monday, due to a database corruption, the rate table could not be updated. At 9:05 a.m., it was identified that the table had errors. A rerun of the update was done, and the table was re-created at 9:55 a.m. Verification was run for 5 minutes. The verification found additional errors and the process had to be repeated. After the second rerun and verification, the rate table became available to the bank branches. What was the availability of the rate table for the week in which this incident took place, assuming there were no other issues?

Answer 1

System run time = 9 -5 PM , 8 hours per day or 40 hours per week

Errors identified at 9:05 AM

Wasted time

Time wasted till identification of error = 5 minutes

Time to rerun = 50 minutes

Verification time = 5 minutes

Second rerun =50 minutes

Second verification = 5 minutes

Total wasted time on Monday = 5 + 50 + 5 + 50 +5 = 115 minutes or 115 / 60 = 1.92 hours , No time wasted on other days of the week

Total available hours = 40 - 1.92 = 38.08

Availability = Available hours / Total = 38.08 /40 = 95.20 %