Multiple realms vs multiple rules with single realm

What’s the best way to protect multiple resources under single domain?

Create separate realm for each resource and allow rule with get/post (separate realm to protect “/test/abc” and “/test/xyz”)

or

single realm with base protected and creating multiple rules under it (create one realm “/test” and 2 rules with /abc* and /xyz*)

Note: We have a need to protect 100s of such realms under single domain. Looking for optimal and best approach without impacting policy server performance.

Thanks

Vijay