$ heroku pg:info
~ $ heroku pg:info -a zundan-mastodon=== DATABASE_URL, PG_HOBBY_BASIC_URL
Plan: Hobby-basic
Status: Available
Connections: 6/20
PG Version: 9.6.1
Created: 2017-04-20 18:31 UTC
Data Size: 270.0 MB
Tables: 35
Rows: 600049/10000000 (In compliance) - refreshing
Puma 3スレッド、Sidekiq 1スレッド、Streaming 2スレッドくらいかな？