Where are the Gluten/Velox caches and how are they cleared?

[sumokiama]

We are running TPCDS against Gluten/Velox/S3/Centos8 on a single server.
We want to clear all caches between query runs but are unaware of what caches are implemented, where they are located and how they are cleared.

We assume:

• Spark query cache may be enabled
• Gluten may have its own cache
• Velox has both a memory and ssd cache

Is this correct?
How do we clear caches?