Node caching is useful when the same runtime is needed for a series of steps, and the same large set of dependencies needs to be installed. Node caching, which is available for dynamic node pools, helps speed up the execution of your builds and saves time by preserving the runtime environment for subsequent steps to execute in. For example, Docker layers can be cached, leading to faster docker builds since those layers don’t need to be rebuilt each time.
When adding a dynamic node pool, node caching can be enabled by clicking the Enable Cache check box. For more information, see Dynamic Node Caching.