This page shows all publications that appeared in the IASI annual research reports. Authors currently affiliated with the Institute are always listed with the full name.

You can browse through them using either the links of the following line or those associated with author names.

Show all publications of the year  2015, with author Bonifaci V., in the category IASI Research Reports (or show them all):

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IASI Research Report n. 15-05  (Previous ) 


Melani A., Bertogna M., Vincenzo Bonifaci, Marchetti Spaccamela A., Buttazzo G.C.

Memory-Processor Co-Scheduling in Fixed Priority Systems

ABSTRACT

A major obstacle towards the adoption of multi-core plat- forms for real-time systems is given by the difficulties in characterizing the interference due to memory contention. The simple fact that multiple cores may simultaneously ac- cess shared memory and communication resources introduces a significant pessimism in the timing and schedulability anal- ysis. To counter this problem, predictable execution mod- els have been proposed splitting task executions into two consecutive phases: a memory phase in which the required instruction and data are pre-fetched to local memory (M- phase), and an execution phase in which the task is exe- cuted with no memory contention (C-phase). Decoupling memory and execution phases not only simplifies the timing analysis, but it also allows a more efficient (and predictable) pipelining of memory and execution phases through proper co-scheduling algorithms. In this paper, we take a first step towards the design of smart co-scheduling algorithms for sporadic real- time tasks complying with the M/C (memory-computation) model. We provide a theoretical framework that aims at tightly characterizing the schedulability improvement ob- tainable with the adopted M/C task model on a single-core systems. We identify a tight critical instant for M/C tasks scheduled with fixed priority, providing an exact response- time analysis with pseudo-polynomial complexity. We show in our experiments that a significant schedulability improve- ment may be obtained with respect to classic execution mod- els, placing an important building block towards the design of more efficient partitioned multi-core systems.