Checkpoint Placement for Systematic Fault-Injection Campaigns

Tim-Marek Thomas (Leibniz Universität Hannover),
Christian Dietrich (Technische Universität Hamburg-Harburg),
Matthias Mnich (Technische Universität Hamburg-Harburg),
Daniel Lohmann (Leibniz Universität Hannover)

FI campaigns require many independent experiments and, combined, long run
times. One cost factor is the time required to bring the system-under test into
the fault-free state at injection time. A technique to speed up the forwarding
phase are checkpoints. We show that the placement of checkpoints has a
significant influence on the achieved savings, especially if the planned faults
are non-uniformly distributed. For this, we discuss the checkpoint-selection
problem in general, formalize it as a 2-dimensional Knapsack problem, and
propose a checkpoint-selection method. Our evaluation shows that our approach
consistently reduces the forward-phase cycles, and with 16 checkpoints we
reduce the needed cycles by at least 89 percent and up to 99.989 percent.