Performance testing using Selenium and WebDriver is generally not advised. Not because it is incapable, but because it is not optimised for the job and you are unlikely to get good results.
The other potential attraction is “saving time” — carrying out functional and performance tests at the same time. However, functional and performance tests have opposing objectives. To test functionality, a tester may need to be patient and wait for loading, but this will cloud the performance testing results and vice versa.
Example (open source) packages to use are: JMeter