this post was submitted on 13 Jun 2023
13 points (93.3% liked)
PHP
538 readers
1 users here now
Welcome to /c/php! This is a community for PHP developers and enthusiasts to share and discuss anything related to PHP. From the latest updates and tutorials, to your burning questions and amazing personal projects, we welcome all contributions.
Let's foster an environment of respect, learning, and mutual growth. Whether you're an experienced PHP developer, a beginner, or just interested in learning more about PHP, we're glad to have you here!
Let's code, learn, and grow together!
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Can anyone here help me understand persistent PDO connections?
So I set up Patroni cluster, everything works as expected. But during the failover/switchover PHP remembers connections to the failed node. And I can't figure out why. Reloading FPM is kind of PitA.
I will use PgBouncer. But I still would like to know how PHP works with the persistent connections.
Honestly I don't know much about this but I think this can occur because PHP (or more specifically, the PDO extension) isn't necessarily aware of the health of the PostgreSQL node it's connected to. From PHP's perspective, it opened a connection, and unless explicitly told otherwise, it will assume the connection remains open. The Patroni switchover/failover is happening independently of PHP. PgBouncer is probably a good solution for this.
If I knew how to invalidate failed connection in the persistent pool, that would be enough.