.Net 5.0: upgrading from 5.0.2 -> 5.0.5 leads to '53300: sorry, too many clients already'

Issue:

1. currently running .net 5.0, and after upgrading to Npgsql.EntityFrameworkCore.PostgreSQL 5.0.5, connection strings are not disposed of, leading to an exception: ‘53300: sorry, too many clients already’.

Workaround:

1. Downgrading to Npgsql.EntityFrameworkCore.PostgreSQL 5.0.2

Tested: For 5.0.2 and 5.0.5, completed the following steps:

1. ran pg_stat_activity query to see current db connections

SELECT *
FROM   pg_stat_activity
order by "backend_start"

1. run 10 queries using ef core
2. re-run pg_stat_activity query to see connections

Test Result:

1. 5.0.2 - 2 connection remains idle
2. 5.0.5 - 10 connections remain idle

[taspeotis]

I recommend downgrading to Npgsql.EntityFrameworkCore.PostgreSQL 5.0.4

I mentioned downgrading to 5.0.4 on another issue but I was a bit inaccurate (sorry) - the next earlier version on NuGet is 5.0.2. Downgrading to that fixed the issue.

[taspeotis]

There’s at least one connection leak in 5.0.5