I’ve updated puma to using phased-restart. Phased restart only restart worker, master process not load and have an error like below when old release folder have been removed.

["/var/www/proj/shared/bundle/ruby/2.5.0/gems/wkhtmltopdf-binary-0.12.4/bin/wkhtmltopdf", "-q", "--zoom", "0.7", "--margin-top", "0", "--margin-bottom", "0", "--margin-left", "0", "--margin-right", "0", "file:////tmp/wicked_pdf20240916-9256-10of6ll.html", "/tmp/wicked_pdf_generated_file20240916-9256-bz4g9w.pdf"]
Error: PDF could not be generated!
 Command Error: /home/deploy/.rvm/rubies/ruby-2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.4/lib/bundler/definition.rb:33:in `build': /var/www/proj/releases/20240913043719/Gemfile not found (Bundler::GemfileNotFound)
  from /home/deploy/.rvm/rubies/ruby-2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.4/lib/bundler.rb:135:in `definition'
  from /home/deploy/.rvm/rubies/ruby-2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.4/lib/bundler.rb:101:in `setup'
  from /home/deploy/.rvm/rubies/ruby-2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.4/lib/bundler/setup.rb:20:in `<top (required)>'
  from /home/deploy/.rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
  from /home/deploy/.rvm/rubies/ruby-2.5.1/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'

It seems that wicked_pdf uses the master process to gender the pdf without using worker processes?