Nginx Server Optimization & Error Resolution

I'm in need of a Linux server expert to address an issue I am currently experiencing with my server. Specifically, I'm tackling two major problems: performance issues and a persistent 'Too Many Open Files' error.

Specific task details:
* Investigate and fix 'Too Many Open Files' server error
* Optimize server performance for my web-based applications

Skills and Expertise Required:
* Extensive experience with Linux server management
* Proficiency in dealing with Nginx server software
* Substantial knowledge in handling and resolving server errors
* Proven track record in server performance optimization

The ideal candidate is not just a problem-solver but also gives specific suggestions to prevent future similar server issues.