1.74.0 - PostgreSQL - Cannot use a pool after calling end on the pool

[kuzzmi]

Bug Description

After upgrading self-hosted version to 1.74.0 (to have a fix for PG connection issues, so I can add a lot of data at once), I see other issues:

{
  "errorMessage": "Cannot use a pool after calling end on the pool",
  "errorDescription": "Cannot use a pool after calling end on the pool",
  "errorDetails": {},
  "n8nDetails": {
    "time": "08/01/2025, 19:56:42",
    "n8nVersion": "1.74.0 (Self Hosted)",
    "binaryDataMode": "default",
    "cause": {}
  }
}

To Reproduce

After X minutes of establishing the first connection, all PG nodes fail with provided error message.

Expected behavior

When pool is closed, reopen a new pool.

Operating System

Debian 12

n8n Version

1.74.0

Node.js Version

v20.18.1

Database

SQLite (default)

Execution mode

main (default)

[Joffcom]

Hey @kuzzmi,

We have created an internal ticket to look into this which we will be tracking as "N8N-8064"

[kuzzmi]

Realized that this happens much much more often with Postgres as a chat memory. If I find anything more useful, will append to the issue..

[neilsonsdsouza]

Same problem

[neilsonsdsouza]

When I use the version prior to 1.74 this error does not appear

[ams330dev]

Same issue for me as well, after update with the chat memory node. Had to return to window buffer memory.

[g-roliveira]

I am facing the same issue when using **PostgresChatMemory** in an AI agent with pre-release version 1.74.1. The issue does not occur in version 1.73.

Issue details:

On the first interaction, the connection is opened and works correctly.
On subsequent interactions, the connection cannot be used, apparently due to issues with reusing the connection pool.

Steps to reproduce:

Set up anAI agentusing PostgresChatMemory.
Run the first interaction (it works fine).
Try to run additional interactions (fails to reuse the connection pool).

Environment:

Version: 1.74.1 (pre-release)

Expected behavior:

The connection pool should be reused correctly in all interactions.

Current behavior:

Only the first interaction works; subsequent interactions fail when trying to reuse the connection pool.

Additional information:

This issue does not occur in version 1.73.
The problem is suspected to be related to connection pool management in the new version.

[netroy]

This will likely be fixed in #12484.

[netroy]

Can you folks try upgrading to 1.74.2 or 1.75.1 🙏🏽

[kuzzmi]

@netroy Just installed 1.75.1, will see how it goes. Thanks folks for addressing that!

[diegoele]

Still not working for me in version 1.75.1

[g-roliveira]

The problem still persists for me in version 1.74.2 and 1.75.1

[netroy]

Please try upgrading to 1.74.3 or 1.75.2 🙏🏽

[g-roliveira]

Validated using 1.74.3 - It works!
Validated using 1.75.2 - It works!

Great job, guys!