whenever gem and scheduling a job every n min starting at an offset

It sounds like you have a dependency between the two jobs, so there are two ways I think you can handle this. If you want to run at 1,6,11,16 and so on, as your question suggests, then simply use raw cron syntax:

every '0,5,10,15,20,25,30,35,40,45,50,55 * * * *' do  command "echo 'you can use raw cron syntax one'"endevery '1,6,11,16,21,26,31,36,41,46,51,56 * * * *' do  command "echo 'you can use raw cron syntax two'"end

But it's probably better to execute the second job once the first one is done. This should ensure that the jobs don't overlap and that the second only runs when after the first completes.

every 5.minutes do  command "echo 'one' && echo 'two'"end

every expects an integer.

To avoid thundering herd problem, you can do this.

every 5.minutes - 10.seconds do  command "echo first task"endevery 5.minutes + 10.seconds do  command "echo second task"end

You can randomise the offset too

def some_seconds  (-10..10).to_a.sample.secondsendevery 5.minutes + some_seconds do  command "echo first task"endevery 5.minutes + some_seconds do  command "echo second task"end

Like other answers this won't work for tasks depending on each other. If your tasks depend on each other, you should use rake to handle it for you or run next one manually in your task.

# shedule.rbevery 5.minutes do  rake 'jobs:last_one'end# Rakefile.rbnamespace :jobs do  task :first_one do    sh 'first command'  end  task second_one: [:first_one] do    sh 'second_command that_should_run_after_first_one'  end  task last_one: [:second_one] do    sh 'last_command that_should_run_after_all_commands'  endend

Yes, that should be valid. Look at https://github.com/javan/whenever/blob/master/lib/whenever/cron.rb

Look at the parse_time method. These lines in particular:

      when 1.hour...1.day        hour_frequency = (@time / 60 / 60).round        timing[0] = @at.is_a?(Time) ? @at.min : @at        timing[1] = comma_separated_timing(hour_frequency, 23)