We’re considering using AWS Aurora Serverless PostgresSQL for our developer environment. I’ve already determined that it will meet our needs as far as Postgres compatibility, but I’m looking for help getting over the last inconvenience. Whenever the DB is idle for a certain amount of time, it spins …

Reading the docs, I got the idea that the queue_ options are for preventing overload, but found a interesting one: after_connect_timeout The maximum time allowed to perform function specified by :after_connect option (default: 15_000 ). There is also a configure option, that you can use to print…

Ah, so if after_connect blocks, I could use it to wait for the connection to actually return something, with an after_connect_timeout of 60 seconds or so. Worth a try. Thank you!

I haven’t really solved it yet. I’ve got an acceptable (for our purposes) workaround, but it’s not great. In my application’s Ecto.Repo implementation, I added two functions: def wait_for_connection do Logger.info("Waiting for active database connection...") canary() |> WaitForIt.wait(tim…

What about waiting for Postgres to spin up before starting the application? If you’re using docker-compose have one of the containers talk to Postgres until it’s up and once it does trigger the application to start up.

I’m not running that way. Everything is running on AWS. The database autoscales – it spins down when it’s idle for more than a particular period of time, and the only way to spin it back up is to attempt a connection. I could probably have the process that starts my app wait for the connection inst…

Ah I see. I’m still trying to figure out exactly what is happening in your case. The error you showed in your first post means that your process tried to get a connection from the pool but it waited too long and stopped trying: ** (DBConnection.ConnectionError) connection not available and request…

Elixir Programming Language Forum

Have Ecto wait for DB to spin up?

Questions & Help Questions

elixirium August 23, 2022, 11:57am 4

@mbklein I’ve run into similar challenges. How did you solve this problem?