Abstract— This article presents some results about schedulability analysis of tasks with offsets also known as transactions, in the particular case of monotonic transactions. The impact of a transaction on the response time of a lower priority task under analysis is computed with the interference implied by the transaction. In the general context of tasks with offsets (general transactions), only exponential methods are known to calculate the exact worst-case response time of a task. However, in this case, Mäki-Turja and Nolin have proposed an efficient approximation method. A monotonic pattern in a transaction (regarding the priority of the task under analysis), occurs when, by rotation of the higher priority tasks in a transaction, it is possible to find a pattern of tasks such that the processor demand of the transaction is monotically decreasing during a period of the transaction. We have shown in our previous work that if a task under analysis is such that all the interfering...