  In Software-Defined Networking (SDN)-enabled cloud data centers, live
migration is a key approach used for the reallocation of Virtual Machines (VMs)
in cloud services and Virtual Network Functions (VNFs) in Service Function
Chaining (SFC). Using live migration methods, cloud providers can address their
dynamic resource management and fault tolerance objectives without interrupting
the service of users. However, in cloud data centers, performing multiple live
migrations in arbitrary order can lead to service degradation. Therefore,
efficient migration planning is essential to reduce the impact of live
migration overheads. In addition, to prevent Quality of Service (QoS)
degradations and Service Level Agreement (SLA) violations, it is necessary to
set priorities for different live migration requests with various urgency. In
this paper, we propose SLAMIG, a set of algorithms that composes the
deadline-aware multiple migration grouping algorithm and on-line migration
scheduling to determine the sequence of VM/VNF migrations. The experimental
results show that our approach with reasonable algorithm runtime can
efficiently reduce the number of deadline misses and has a good migration
performance compared with the one-by-one scheduling and two state-of-the-art
algorithms in terms of total migration time, average execution time, downtime,
and transferred data. We also evaluate and analyze the impact of multiple
migration planning and scheduling on QoS and energy consumption.
