Octopus doesn't work with Rails' schema cache

[nebel95]

I am using Rails 5 + Unicorn + Octopus with 3 Postresql database shards (all of them share the same schema). Everything seems to work well but I cannot seem to get schema cache to work, my database shards are always hit by queries like below when a web worker is started (I think the correct behavior should be no query at all):

SELECT a.attname
FROM
  (SELECT indrelid,
          indkey,
          generate_subscripts(indkey, $1) idx
   FROM pg_index
   WHERE indrelid = $2::regclass
     AND indisprimary ) i
JOIN pg_attribute a ON a.attrelid = i.indrelid
AND a.attnum = i.indkey[i.idx]
ORDER BY i.idx;

Is this a bug with octopus or am I doing something wrong here? I have schema cache enabled with config.active_record.use_schema_cache_dump = true in my Rails config file. Below is my Unicorn config:

preload_app true

after_fork do |server, worker|
  # START OF OCTOPUS SPECIFIC CONFIG
  ActiveRecord::Base.connection_proxy.initialize_shards(Octopus.config)
  # END OF OCTOPUS SPECIFIC CONFIG
end

[samerzmd]

We are facing the same issue