Abstract
In this paper we consider a spin-based multiprocessor
locking protocol, named the Multiprocessor resource
sharing Protocol (MrsP). MrsP adopts a helping-mechanism
where the preempted resource holder can migrate. The original
schedulability analysis of MrsP carries considerable pessimism
as it has been developed assuming limited knowledge of the
resource usage for each remote task. In this paper new MrsP
schedulability analysis is developed that takes into account such
knowledge to provide a less pessimistic analysis than that of
the original analysis. Our experiments show that, theoretically,
the new analysis offers better (at least identical) schedulability
than the FIFO non-preemptive protocol, and can outperform
FIFO preemptive spin locks under systems with either intensive
resource contention or long critical sections.
The paper also develops analysis to include the overhead of
MrsP’s helping mechanism. Although MrsP’s helping mechanism
theoretically increases schedulability, our evaluation shows that
this increase may be negated when the overheads of migrations
are taken into account. To mitigate this, we have modified
the MrsP protocol to introduce a short non-preemptive section
following migration. Our experiments demonstrate that with
migration cost, MrsP may not be favourable for short critical
sections but provides a better schedulability than other FIFO
spin-based protocols when long critical sections are applied.
locking protocol, named the Multiprocessor resource
sharing Protocol (MrsP). MrsP adopts a helping-mechanism
where the preempted resource holder can migrate. The original
schedulability analysis of MrsP carries considerable pessimism
as it has been developed assuming limited knowledge of the
resource usage for each remote task. In this paper new MrsP
schedulability analysis is developed that takes into account such
knowledge to provide a less pessimistic analysis than that of
the original analysis. Our experiments show that, theoretically,
the new analysis offers better (at least identical) schedulability
than the FIFO non-preemptive protocol, and can outperform
FIFO preemptive spin locks under systems with either intensive
resource contention or long critical sections.
The paper also develops analysis to include the overhead of
MrsP’s helping mechanism. Although MrsP’s helping mechanism
theoretically increases schedulability, our evaluation shows that
this increase may be negated when the overheads of migrations
are taken into account. To mitigate this, we have modified
the MrsP protocol to introduce a short non-preemptive section
following migration. Our experiments demonstrate that with
migration cost, MrsP may not be favourable for short critical
sections but provides a better schedulability than other FIFO
spin-based protocols when long critical sections are applied.
| Original language | English |
|---|---|
| Title of host publication | 2017 IEEE 23rd International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA) |
| Publisher | IEEE |
| Pages | 1 |
| Number of pages | 10 |
| ISBN (Electronic) | 978-1-5386-1898-1 |
| DOIs | |
| Publication status | Published - 2017 |
| Event | IEEE International Conference on Embedded and Real-Time Computing Systems and Applications - Duration: 1 Sept 2017 → … |
Conference
| Conference | IEEE International Conference on Embedded and Real-Time Computing Systems and Applications |
|---|---|
| Abbreviated title | RTCSA |
| Period | 1/09/17 → … |