Is it possible to save the DB to disk and memory at the same time so that reads are only from memory?

If I use this code:

package main

import (
	"log"

	badger "github.com/dgraph-io/badger/v3"
)

func main() {
  // Open the Badger database located in the /tmp/badger directory.
  // It will be created if it doesn't exist.
  db, err := badger.Open(badger.DefaultOptions("/tmp/badger"))
  if err != nil {
	  log.Fatal(err)
  }
  defer db.Close()
  // Your code here…
}

I understand that badger writes the data to disk but what about reads? does it also read it from disk? or does it make a copy in memory and read it from there?

What happens is that I want to perform reads in memory but at the same time persist the data on disk if the server shuts down.