database.yml

<%
  # Quick function to calculate the correct number DB_POOL size. DB_POOL size is
  # reused for the puma web server and sidekiq. It cannot be less than the
  # amount the concurrency of either.

  db_needed_for_web     = ENV.fetch('WEB_CONCURRENCY', 1) * ENV.fetch('WEB_THREADS', 1)
  db_needed_for_sidekiq = ENV.fetch('SIDEKIQ_CONCURRENCY', 0)

  # The minimum pool size is the maximum of the sidekiq and web concurrency. We
  # add some extras to the pool for sidekiq's scheduler and one off dynos.
  min_pool_size_needed  = [db_needed_for_web, db_needed_for_sidekiq].max + 5

  # db pool size
  db_pool_size = ENV["DB_POOL"] || min_pool_size_needed
%>


development:
  adapter: postgresql
  database: education_web_development
  encoding: unicode
  host: localhost
  port: <%= ENV['BOXEN_POSTGRESQL_PORT'] || 5432 %>
  pool: 30

test:
  adapter: postgresql
  database: education_web_test
  encoding: unicode
  host: localhost
  port: <%= ENV['BOXEN_POSTGRESQL_PORT'] || 5432 %>

staging:
  encoding: utf8
  pool: <%= db_pool_size %>

production:
  encoding: utf8
  pool: <%= db_pool_size %>