Horizontal Scaling

Introduction to Sharding

When Sveltos is managing hundreds of clusters and thousands of applications, it is recommended to adopt a sharding strategy to distribute the load across multiple Sveltos controller instances.

Sveltos has a controller running in the management cluster called the shard controller. It watches for cluster annotations. When it detects a new cluster shard, the shard controller automatically deploys a new set of Sveltos controllers to manage the shard.

How does Sveltos distribute the load? This is done by adding the special annotation sharding.projectsveltos.io/key to the managed clusters of interest. By default, all clusters are managed by the same Sveltos controller. When no more managed clusters have a special annotation set, Sveltos automatically brings down the extra Sveltos controllers.

For more information, have a look at the .gif below.

Sharding Benefits

The benefits of using a sharding strategy include:

1. Improved performance: By distributing the load across multiple instances of Sveltos controllers, sharding can improve the performance of Sveltos.
2. Increased scalability: Sharding allows Sveltos to manage a larger number of managed clusters and applications.
3. Reduced risk: If one instance of a Sveltos controller fails, the other instances can continue to manage the applications in their respective cluster shards.