## 3 Problem Description and Proposed Solution
### Method of the Proposed Approach
#### 3.2.3 Optimized PC Algorithm Based on Knowledge Graph
; Formal analysis, J.Q. ; Investigation, J.Q. ; Methodology, J.Q. and K.Y. ; Resources, S.-L.Z. ; Software, S.-L.Z. ; Supervision, Q.D. ; Validation, J.Q. and S.-L.Z. ; Writing--original

\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Number of KPIs** & \multicolumn{3}{c}{**20**} & \multicolumn{3}{c}{**50**} & \multicolumn{3}{c}{**100**} \\ \hline
**Resource Usage/** & **Time** & **CPU** & **MEM** & **Time** & **CPU** & **MEM** & **Time** & **CPU** & **MEM** \\
**Rows of Records** & **(s)** & **(\%)** & **(MB)** & **(s)** & **(\%)** & **(MB)** & **(s)** & **(\%)** & **(MB)** \\ \hline
25 & 4.36 & 7.92 & 17.92 & 10.46 & 7.94 & 34.19 & 15.18 & 8.56 & 33.86 \\
50 & 4.38 &



draft, J.Q. ; Writing--review and editing, Q.D. and C.Q. All authors have read and agreed to the published version of the manuscript. This work has been supported by the National Natural Science Foundation of China (Grant No. 61672384). We have to acknowledge the OPNFV project from Linux open source foundation because some of the ideas come from the OPNFV community. We have obtained lots of inspiration and discussion. Last but not least, the authors thank the open source project Sock Shop which provided strong support for our experiments. Finally, the authors are grateful for the comments and reviews from the reviewers and editors

The authors declare no conflict of interest

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