The rapid growths in demand for computing
resources and shift to Cloud Computing (CC) paradigm
have necessitated the establishment of Virtualized Data
Centers (DCs) known as Server Farms. In these centers,
computing resources are virtualized, which consequently
consume enormous electrical energy. This theoretical
review presents background information and assess
topic in a state of flux relating to energy-saving criteria
in DCs using Ant Colony System (ACS) algorithms. The
purpose is to avail its readership both early and mid-
career researchers in computer discipline; critical
literature review, existing research gaps and
comprehensive bibliography as reference materials.
Also, a literature review on other energy reduction using
greedy approaches is included. Furthermore, sources of
this review, research tools used by previous authors,
adopted energy-saving strategies, taxonomy of ACS
variants and reputable World’s publishers were
analyzed. These are expected to pave way for the laying
foundation in future research works.
Keywords : Cloud Computing, Virtualization, Virtualized Data Centers, Virtual Machine Consolidation/Placement, Ant Colony System.