Reduce CPU and GC overheads in Metadata

Description

avoid toLowerCase invocation if it is possible to reduce CPU usage and GC overheads in Metadata class:

The operation is quite simple but invokes very frequently.

The following traces are collected using async java profiler for a real application.
toLowerCase from DataStax driver takes about 1.8% CPU in total

Environment

None

Pull Requests

None
Fixed

Assignee

Unassigned

Reporter

Dmitry Konstantinov

Labels

PM Priority

None

Affects versions

Fix versions

Doc Impact

None

Size

None

External issue ID

None

External issue ID

None

Components

Priority

Major
Configure