MySQL Dump Importing Speed Super Slow for my Kuberenetes MySQL Pod

Cluster information:

Kubernetes version: v1.20.9
Cloud being used: Openstack
Installation method: Rancher with Portworx Storage
Host OS: Ubuntu 20.04.2 LTS & Ubuntu 20.04.3 LTS
CNI and version: calico v3.17.2
CRI and version: docker://20.10.7
MySQL version: v5.7
File System: btrfs

The MySQL dump insert speed to kubernetes MySQL container is super slow. A 1.8GB dump takes more than 5 hours to complete.

I use the following command to insert the dump to the pvc of the pod

kubectl exec -it [podname] -n [namespace] -- mysql -u [db user] -p[password] [db name] < [name of the dump].sql

Is there any performance tuning method for MySQL kubernetes or it is known behavior when performing dump to Kubernetes pod?