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

Managed Connection Pooling lets you scale your workloads by optimizing resource useand connection latency for your Cloud SQL instances using pooling.Managed Connection Pooling creates a pool of threads to handleincoming requests. This provides significant performance improvements,especially for scaled connections, by absorbing sudden connection spikes withoutoverloading the server with a growth in the number of threads.

For more information about enabling Managed Connection Pooling, seeConfigure 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 ofMYSQL_$version.R20250531.01_10. For more information about performing self-service maintenance, seePerform self-service maintenance.

Advanced configuration options

You cancustomize Managed Connection Poolingby modifying themax_pool_size configuration option.

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

Limitations

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

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

What's next

• Create an instance
• Configure Managed Connection Pooling