Configure Project UDFs Cache Settings
Audience: System Administrators
Content Summary: This page outlines the configuration for setting up project UDFs, which allow users to set their current project in Immuta through Spark. For details about the specific functions available and how to use them, see the Use Project UDFs (Databricks) page.
Use Project UDFs in Databricks
Currently, caches are not all invalidated outside of Databricks because Immuta caches information pertaining to a user's current project in the NameNode plugin and in Vulcan. Consequently, this feature should only be used in Databricks.
Web Service and On-Cluster Caches
Immuta caches a mapping of user accounts and users' current projects in the Immuta Web Service and on-cluster. When users change their project with UDFs instead of the Immuta UI, Immuta invalidates all the caches on-cluster (so that everything changes immediately) and the cluster submits a request to change the project context to a web worker. Immediately after that request, another call is made to a web worker to refresh the current project.
To allow use of project UDFs in Spark jobs, raise the caching on-cluster and lower the cache timeouts for the Immuta Web Service. Otherwise, caching could cause dissonance among the requests and calls to multiple web workers when users try to change their project contexts.
1 - Lower Web Service Cache Timeout
- Click the App Settings icon in the left sidebar and scroll to the HDFS Cache Settings section.
Lower the Cache TTL of HDFS user names (ms) to 0.
2 - Raise Cache Timeout On-Cluster
In the Spark environment variables section, set the
IMMUTA_PROJECT_CACHE_TIMEOUT_SECONDS to high values (like
Note: These caches will be invalidated on cluster when a user calls
immuta.set_current_project, so they can
effectively be cached permanently on cluster to avoid periodically reaching out to the web service.