Databricks system design clarification needed

Hey Databricks folks, I have a few questions about the system design and architecture rounds and would appreciate any pointers.

1. Sys design- I understand this is mostly about low level, single node design problems revolving around concurrency. Is knowledge of mutex, semaphore, conditional variables, blocking queues etc. enough for this round or is something more needed?
(If any of you remember the materials you used to prepare and are willing to share, that would be great too)

2. Architecture- this I believe is the large scale system design round. Are questions usually from product side of the story i.e. design whatsapp, design Google Docs etc. or more focused on infra e.g. design a distributed file system, design a distributed job scheduler?

5 yoe, ~300k