Solve memory leak & HTTP timeout for Ruby App

Project status:
We have built a Ruby App (v 2.2.1) using ElasticSearch / Redis / Puma / Sidekiq / etc. The website is live and hosted on Heroku.
Even after fixing n+1 queries, we encounter memory leak issue.
We used TunemyGC add-on and now we are facing troubleshooting with request timeouts.

Work to be done:
We wil need you to dig into the existing code to find out a solution to increase website performance and make sure we can drive more traffic without any problem.

Deadlines: end of December