"SET SEARCH_PATH" Transaction Hangs in Idle State in Postgres

[ixipixi]

Describe the bug

When Metabase launches a query is executed against the app db to set the "search_path" variable in Postgres. The transaction never leaves the "idle in transaction" state.

To Reproduce

1. Start Metabase v48.5 or higher
2. On the application database run:

SELECT pid ,datname ,usename ,application_name ,client_hostname ,client_port ,backend_start ,query_start ,query ,state
FROM pg_stat_activity
WHERE state = 'idle in transaction';

Note that the pid with the "set search_path" query in it never resolves.

Expected behavior

The transaction should complete.

Logs

No response

Information about your Metabase installation

{
  "browser-info": {
    "language": "en-US",
    "platform": "Win32",
    "userAgent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
    "vendor": "Google Inc."
  },
  "system-info": {
    "file.encoding": "UTF-8",
    "java.runtime.name": "OpenJDK Runtime Environment",
    "java.runtime.version": "11.0.23+9",
    "java.vendor": "Eclipse Adoptium",
    "java.vendor.url": "https://adoptium.net/",
    "java.version": "11.0.23",
    "java.vm.name": "OpenJDK 64-Bit Server VM",
    "java.vm.version": "11.0.23+9",
    "os.name": "Linux",
    "os.version": "5.15.133.1-microsoft-standard-WSL2",
    "user.language": "en",
    "user.timezone": "GMT"
  },
  "metabase-info": {
    "databases": [
      "h2",
      "postgres"
    ],
    "hosting-env": "unknown",
    "application-database": "postgres",
    "application-database-details": {
      "database": {
        "name": "PostgreSQL",
        "version": "11.22 (Debian 11.22-1.pgdg110+1)"
      },
      "jdbc-driver": {
        "name": "PostgreSQL JDBC Driver",
        "version": "42.7.2"
      }
    },
    "run-mode": "prod",
    "version": {
      "date": "2024-05-09",
      "tag": "v1.49.9",
      "hash": "c0913c7"
    },
    "settings": {
      "report-timezone": null
    }
  }
}

Severity

Unclear on if this impacts anything other than leaving a single process hanging since this is already the default setting for this value in Postgres

Additional context

No response

[darksciencebase]

@ixipixi is this a neatness issue or was there some particular fallout from this? thinking about the priority here and would like to understand the whole picture

[ixipixi]

@darksciencebase it's not impacting performance afaik but it creates an inconvenience for customers/sys admins/dbas that are monitoring for hanging transactions. They see a transaction stuck in idle for a long time and go research it to discover it's this every time. They know to ignore it but it's not ideal.