Delayed_job: On error, the job is scheduled again in 5 seconds + N ** 4, where N is the number of attempts. https://github.com/collectiveidea/delayed_job

attempts.rb

def time(n)
  5 + n ** 4
end

total_hours = 0

25.times do |n|
  seconds = time(n)
  puts "---------- #{n} ---------"
  puts "Seconds: #{seconds}"
  
  hours = seconds/60.0/60.0
  puts "Hours: #{hours}"
  
  total_hours += hours
  puts "Total hours: #{total_hours}"
  
  puts "Total days: #{total_hours/24.0}"
  puts
end

output.txt

---------- 0 ---------
Seconds: 5
Hours: 0.0013888888888888887
Total hours: 0.0013888888888888887
Total days: 5.7870370370370366e-05

---------- 1 ---------
Seconds: 6
Hours: 0.0016666666666666668
Total hours: 0.0030555555555555553
Total days: 0.0001273148148148148

---------- 2 ---------
Seconds: 21
Hours: 0.005833333333333333
Total hours: 0.008888888888888887
Total days: 0.0003703703703703703

---------- 3 ---------
Seconds: 86
Hours: 0.02388888888888889
Total hours: 0.03277777777777778
Total days: 0.001365740740740741

---------- 4 ---------
Seconds: 261
Hours: 0.0725
Total hours: 0.10527777777777778
Total days: 0.004386574074074074

---------- 5 ---------
Seconds: 630
Hours: 0.175
Total hours: 0.28027777777777774
Total days: 0.011678240740740739

---------- 6 ---------
Seconds: 1301
Hours: 0.36138888888888887
Total hours: 0.6416666666666666
Total days: 0.02673611111111111

---------- 7 ---------
Seconds: 2406
Hours: 0.6683333333333333
Total hours: 1.31
Total days: 0.05458333333333334

---------- 8 ---------
Seconds: 4101
Hours: 1.1391666666666667
Total hours: 2.4491666666666667
Total days: 0.10204861111111112

---------- 9 ---------
Seconds: 6566
Hours: 1.823888888888889
Total hours: 4.273055555555556
Total days: 0.17804398148148148

---------- 10 ---------
Seconds: 10005
Hours: 2.779166666666667
Total hours: 7.052222222222222
Total days: 0.2938425925925926

---------- 11 ---------
Seconds: 14646
Hours: 4.068333333333333
Total hours: 11.120555555555555
Total days: 0.46335648148148145

---------- 12 ---------
Seconds: 20741
Hours: 5.761388888888889
Total hours: 16.881944444444443
Total days: 0.7034143518518517

---------- 13 ---------
Seconds: 28566
Hours: 7.9350000000000005
Total hours: 24.816944444444445
Total days: 1.0340393518518518

---------- 14 ---------
Seconds: 38421
Hours: 10.672500000000001
Total hours: 35.489444444444445
Total days: 1.478726851851852

---------- 15 ---------
Seconds: 50630
Hours: 14.06388888888889
Total hours: 49.553333333333335
Total days: 2.064722222222222

---------- 16 ---------
Seconds: 65541
Hours: 18.20583333333333
Total hours: 67.75916666666666
Total days: 2.823298611111111

---------- 17 ---------
Seconds: 83526
Hours: 23.201666666666664
Total hours: 90.96083333333333
Total days: 3.790034722222222

---------- 18 ---------
Seconds: 104981
Hours: 29.16138888888889
Total hours: 120.12222222222222
Total days: 5.005092592592592

---------- 19 ---------
Seconds: 130326
Hours: 36.20166666666667
Total hours: 156.3238888888889
Total days: 6.513495370370371

---------- 20 ---------
Seconds: 160005
Hours: 44.44583333333333
Total hours: 200.7697222222222
Total days: 8.365405092592592

---------- 21 ---------
Seconds: 194486
Hours: 54.02388888888889
Total hours: 254.7936111111111
Total days: 10.616400462962963

---------- 22 ---------
Seconds: 234261
Hours: 65.0725
Total hours: 319.8661111111111
Total days: 13.327754629629629

---------- 23 ---------
Seconds: 279846
Hours: 77.735
Total hours: 397.6011111111111
Total days: 16.566712962962963

---------- 24 ---------
Seconds: 331781
Hours: 92.1613888888889
Total hours: 489.7625
Total days: 20.406770833333333