Impact on page-cache when using same hostPath volumes in multiple containers

Cluster information:

Kubernetes version: k8s 1.18
Cloud being used: pure-metal

I need to use same hostPath volume across multiple pod containers, where one of my pod will perform read operation and other will perform write operation on same hostPath. The I/O operations will be performed by both pods in same directory location.

In such scenario, I was curious to know what would happen with page cache (active_files)?
This page cache would be shared between the pods ? or each pod will have its own page cache ?
Is there any chance, If I delete one pod (which performs write operation) then page-cache of pod ( performing read operation) will increase ?