> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mylists.cc/llms.txt
> Use this file to discover all available pages before exploring further.

# Neon Connection Pooling & pgBouncer

# Neon Connection Pooling & pgBouncer

When running multi-instance MTVL deployments or serverless frontends, connection management is critical to prevent Postgres connection exhaustion.

***

## Direct vs. Pooled Connection Strings

Neon provides two distinct connection endpoints for every database branch:

```
Direct Endpoint:
postgres://user:pass@ep-cool-cloud-123456.us-east-2.aws.neon.tech/neondb?sslmode=require
                                  ^^^^^^ (Direct to Postgres Compute)

Pooled Endpoint:
postgres://user:pass@ep-cool-cloud-123456-pooler.us-east-2.aws.neon.tech/neondb?sslmode=require
                                         ^^^^^^^ (Routes through pgBouncer)
```

| Feature                        | Direct Endpoint                        | Pooled Endpoint (`-pooler`)              |
| :----------------------------- | :------------------------------------- | :--------------------------------------- |
| **Max Concurrent Connections** | Up to 100-500 (Compute size dependent) | Up to **10,000+**                        |
| **Ideal For**                  | Schema migrations, DDL scripts         | HTTP API servers, GORM backend instances |
| **Pooling Mode**               | None                                   | **Transaction Pooling**                  |
| **Prepared Statements**        | Full support                           | Supported with binary parameter binding  |

***

## Best Practices for MTVL with Neon

1. **Use Pooled DSN for Backend API**: Set `DB_DSN` with `-pooler` for runtime API instances.
2. **GORM Connection Pool Tuning**: Configure GORM connection pool limits inside Go to match your workload:

```go theme={null}
sqlDB, err := database.DB()
if err == nil {
    // SetMaxIdleConns sets the maximum number of connections in the idle connection pool.
    sqlDB.SetMaxIdleConns(10)
    // SetMaxOpenConns sets the maximum number of open connections to the database.
    sqlDB.SetMaxOpenConns(50)
    // SetConnMaxLifetime sets the maximum amount of time a connection may be reused.
    sqlDB.SetConnMaxLifetime(time.Hour)
}
```

3. **Always enforce SSL**: Keep `sslmode=require` enabled in all connection strings.