4

I have deployed a Rails app on Heroku since 2 years without trouble Todays the app crash.

Rails log are:

/app/vendor/bundle/ruby/2.3.0/gems/pg-0.21.0/lib/pg.rb:56:in `initialize': FATAL:  sorry, too many clients already (PG::ConnectionBad)
FATAL:  sorry, too many clients already

My rails app is v5.2.0

I use Heroku with 2 dyno The database is a postgres with "Hobby Dev". I try:

  • To upgrade the database but I got the same error

    heroku addons:create heroku-postgresql:standard-0 --follow DATABASE_URL --app locabri
Creating heroku-postgresql:standard-0 on ⬢ xxxx... !
▸    An error was encountered when contacting the add-on partner to create heroku-postgresql:standard-0: The database you are attempting to follow was not found.

  • to change DB_POOL in env variable

  • heroku pg:info

    === DATABASE_URL
Plan:                  Hobby-dev
Status:                Available
Connections:           0/20
PG Version:            10.6
Created:               2017-05-29 07:40 UTC
Data Size:             138.8 MB
Tables:                12
Rows:                  5748/10000 (In compliance)
Fork/Follow:           Unsupported
Rollback:              Unsupported
Continuous Protection: Off
Region:                Europe
Add-on:                postgresql-regular-79163

But nothing work. I can't do anything on the database because I can't connect on it and and don't know how to restart it. Thanks for your help or question

EDIT

  • heroku pg:killall doesnt work

SOLUTION

I finally find the solution by changing the available dyno !

  heroku ps:scale web=0
  heroku ps:scale web=2
  heroku restart

Now I can check the "connexion leak"

Denis Bolomier
  • 350
  • 2
  • 19
  • 2
    Your application has a "connection leak", so this is an application bug. You'll have to find out why it keeps creating new database connections without ever closing old ones. Upgrading or modifying the database won't help. Raising `max_connections` is the wrong answer, because any limit will eventually be exceeded. – Laurenz Albe Jan 24 '19 at 14:35
  • may be you can try to identify the opening connection from some hints here, https://stackoverflow.com/q/19814740/3230406 Try to find out why the connection might more than 20 concurrently. – V-SHY Jan 24 '19 at 15:32
  • I have the same issue today, unfortunately, none of the solutions above works. – Weihang Jian May 06 '20 at 14:44

1 Answers1

1

Recently I encountered a the same error message for one of my Python apps. I've reached out to Heroku and they acknowledged the error:

FATAL: sorry, too many clients already

"It is generally triggered because the hobby tier databases are a shared resource which means that several databases will share computation and storage from a host. We monitor these regularly and always aim to run them with spare capacity but occasionally coincidental spikes in usage from neighboring databases can cause the host machine to have trouble. This is one of the reasons we don't endorse the hobby tier for use in production applications."

They suggested trying one of the following options:

  1. Provision a new hobby database on the same plan and migrate the data over. This will spin up on a new database host which will mean that you no longer have the same noisy neighbors.
  2. Upgrade to one of the professional plans

I've not tried the 1st option, but the second one solved my issue. This answer shows you how to do the migration step by step.

PythonSherpa
  • 2,560
  • 3
  • 19
  • 40