Managed Connection Pooling overview

This page describes what Managed Connection Pooling is and how to use it to optimize database connection management for your Cloud SQL instances using pooling.

Managed Connection Pooling lets you scale your workloads by optimizing resource use and connection latency for your Cloud SQL instances using pooling. Managed Connection Pooling creates a pool of threads to handle incoming requests. This provides significant performance improvements, especially for scaled connections, by absorbing sudden connection spikes without overloading the server with a growth in the number of threads.

For more information about enabling Managed Connection Pooling, see Configure Managed Connection Pooling .

Requirements

To use Managed Connection Pooling, your instance must meet the following requirements:

• Your instance must be a Cloud SQL Enterprise Plus edition instance.
• Managed Connection Pooling requires a minimum maintenance version number of MYSQL_$version.R20250531.01_10 . For more information about performing self-service maintenance, see Perform self-service maintenance .

Advanced configuration options

You can customize Managed Connection Pooling by modifying the max_pool_size configuration option.

The max_pool_size option controls the amount of concurrency for Managed Connection Pooling. The default value depends on the number of vCPU cores in your instance's machine configuration.

Limitations

When using Managed Connection Pooling with your Cloud SQL Enterprise Plus edition instances, consider these limitations:

• Enabling Managed Connection Pooling on an existing instance results in a database restart.
• When Managed Connection Pooling is enabled for your instance, the value of the thread_cache_size metric is defaulted to 0.

What's next

• Create an instance
• Configure Managed Connection Pooling