  The advances in IC process make future chip multiprocessors (CMPs) more and
more vulnerable to transient faults. To detect transient faults, previous
core-level schemes provide redundancy for each core separately. As a result,
they may leave transient faults in the uncore parts, which consume over 50%
area of a modern CMP, escaped from detection. This paper proposes RepTFD, the
first core-level transient fault detection scheme with 100% coverage. Instead
of providing redundancy for each core separately, RepTFD provides redundancy
for a group of cores as a whole. To be specific, it replays the execution of
the checked group of cores on a redundant group of cores. Through comparing the
execution results between the two groups of cores, all malignant transient
faults can be caught. Moreover, RepTFD adopts a novel pending period based
record-replay approach, which can greatly reduce the number of execution orders
that need to be enforced in the replay-run. Hence, RepTFD brings only 4.76%
performance overhead in comparison to the normal execution without
fault-tolerance according to our experiments on the RTL design of an industrial
CMP named Godson-3. In addition, RepTFD only consumes about 0.83% area of
Godson-3, while needing only trivial modifications to existing components of
Godson-3.
