Availability in Cloud SQL

MySQL   |  PostgreSQL   |  SQL Server

This page describes operations that impact availability in Cloud SQL.

Cloud SQL helps you maximize the uptime of your database without any changes to your application. With a 99.99% uptime SLA and near-zero downtime for several planned operations, Cloud SQL Enterprise Plus edition offers greater resilience and business continuity for your applications.

Maximizing uptime means reducing the downtime for your database. Downtime is typically caused by both planned and unplanned events.

For unplanned events such as a failure of one or more infrastructure components within a zone, Cloud SQL high availability (HA) brings up the database in the secondary zone with the same IP address and no data loss so that applications can resume operations on the database. Cloud SQL high availability is also available for Cloud SQL Enterprise edition. For more information about configuring high availability in Cloud SQL, see About high availability (HA).

For planned events such as maintenance or some instance reconfigurations, Cloud SQL Enterprise Plus edition offers near-zero downtime for primary instances with no application changes or proxy requirements.

Planned operations with near-zero downtime

The following planned operations benefit from the near-zero downtime on a Cloud SQL Enterprise Plus edition primary instance. These downtimes are applicable to both standalone (zonal) and high availability (regional) instances.

• Maintenance, which includes the following operations with sub-second downtime:

  • Automatic maintenance that Cloud SQL performs every quarter
  • Self-service maintenance that you can initiate at any time
  • Maintenance simulation that you can initiate to test the sub-second downtime behavior

• Minor version upgrade
  • Minor version upgrades are part of automatic maintenance and happen with sub-second downtime

• Instance scaling

  • Scale-up: Increase the compute size (vCPU, memory) of your Cloud SQL instance as frequently as needed

  • Scale-down: Reduce the compute size (vCPU, memory) of your Cloud SQL instance infrequently

    Note: If you scale down your instance more than once during a three-hour period, then only the first scale down event benefits from near-zero downtime. Subsequent scale down events experience regular downtime.

• Data cache

  • Enable or disable data cache as frequently as needed

• Edition upgrade

  • Perform an in-place upgrade to Cloud SQL Enterprise Plus edition

What's next

• Learn about high availability (HA)

• Enable or disable high availability (HA)

• Read about disaster recovery (DR)