## 3 Methodology  
In large-scale cloud environments with numerous high-performance computing devices, energy inefficiency becomes a significant concern due to the underutilization of resources. Virtualization addresses this issue by allowing multiple instances of VMs to be hosted on a single physical server, thereby reducing operational costs, power consumption, \begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Considered Resources**} & \multicolumn{4}{c}{**Metrics Used in Evaluation**} \\ \cline{2-10}
**Author** & **CPU** & **RAM** & **Bandwidth** & **Disk** & \begin{tabular}{c} **Energy** \\ **Consume** \\ \end{tabular} & \begin{tabular}{c} **Resource** \\ **Wastage** \\ \end{tabular} & \
\begin{tabular}{c} **SLA** \\ **Active PMs** \\ \end{tabular} &
\begin{tabular}{c} **Number of** \\ **Migrations** \\ \end{tabular} \\ \hline [PERSON] et al. [1] & \(\surd\) & \(\surd\) & \(\surd\) & - & - & \(\surd\) & \(\surd\) & - & \(\surd\) \\ [PERSON] et al. [2] & \(\surd\) & \(\surd\) & \(\surd\) & - & \(\surd\) & \(\surd\) & \(\surd\) & - & \(\surd\) \\ [PERSON] et al. [3] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & \(\surd\) & - & - & - \\ [PERSON] et al. [4] & \(\surd\) & \(\surd\) & \(\surd\) & - & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) \\ [PERSON] et al. [5] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & \(\surd\) & - & \(\surd\) & - \\ [PERSON] [6] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & \(\surd\) & - & \(\surd\) & - \\ [PERSON] [7] & \(\surd\) & \(\surd\) & - & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & - & - \\ [PERSON] et al. [8] & \(\surd\) & - & - & - & \(\surd\) & - & \(\surd\) & \(\surd\) & - \\ [PERSON] et al. [9] & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & - & \(\surd\) & - \\ [PERSON] et al. [10] & \(\surd\) & \(\surd\) & \(\surd\) & - & \(\surd\) & \(\surd\) & \(\surd\) & - & - \\ [PERSON] et al. [11] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & - & \(\surd\) & \(\surd\) \\ [PERSON] et al. [12] & \(\surd\) & - & \(\surd\) & - & \(\surd\) & \(\surd\) & - & \(\surd\) & \(\surd\) \\ [PERSON] et al. [13] & \(\surd\) & - & - & - & \(\surd\) & - & \(\surd\) & \(\surd\) & \(\surd\) \\ [PERSON] et al. [14] & \(\surd\) & - & - & - & \(\surd\) & - & - & \(\surd\) & \(\surd\) \\ [PERSON] et al. [15] & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & - & \(\surd\) & \(\surd\) & \(\surd\) \\ [PERSON] et al. [16] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & \(\surd\) & - & \(\surd\) \\ [PERSON] et al. [17] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & - & \(\surd\) \\ [PERSON] et al. [19] & \(\surd\) & - & - & - & \(\surd\) & - & \(\surd\) & - & \(\surd\) \\ [PERSON] et al. [20] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & - & - & - \\ [PERSON] et al. [22] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & \(\surd\) & - & \(\surd\) \\ [PERSON] et al. [23] & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & \(\surd\) & \(\surd\) \\ [PERSON] et al. [24] & \(\surd\) & \(\surd\) & \(\surd\) & - & - & \(\surd\) & - & - & \(\surd\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Resources and evaluation metrics used by authors in the literature. and resource wastage. To further improve resource utilization, underutilized servers can be transitioned to a low-power state. VMP aims to minimize the number of physical servers required to host VMs while generating migration maps for live migration. However, the excessive migration of VMs during consolidation may degrade application performance and response times. Additionally, efforts to minimize energy consumption through VM consolidation may inadvertently violate the SLA between service providers and customers. Figure 1 gives an example of improved VM placement aiming at reducing the power consumption and resource wastage. In this figure, 9 VMs are placed on 4 different PMs utilizing resources to some extent. It can be seen that the PMs' resources are not utilized properly.