  Spot instances offer a cost-effective solution for applications running in
the cloud computing environment. However, it is challenging to run long-running
jobs on spot instances because they are subject to unpredictable evictions.
Here, we present Spot-on, a generic software framework that supports
fault-tolerant long-running workloads on spot instances through checkpoint and
restart. Spot-on leverages existing checkpointing packages and is compatible
with the major cloud vendors. Using a genomics application as a test case, we
demonstrated that Spot-on supports both application-specific and transparent
checkpointing methods. Compared to running applications using on-demand
instances, it allows the completion of these workloads for a significant
reduction in computing costs. Compared to running applications using
application-specific checkpoint mechanisms, transparent checkpoint-protected
applications reduce runtime by up to 40%, leading to further cost savings of up
to 86%.
