EdenFS Caching Flow

Traditionally, EdenFS's caching flow has followed a hierarchical structure, where caches are checked in a sequential manner.

How the Caching Flow is different for CASC?

A few important differences include:

• Optimized Cache Flow: By leveraging knowledge of blob sizes in advance and counting bloom filter prediction, CASC's cache flow has been optimized to bypass unnecessary lookups, resulting in improved efficiency.
• Key Feature: The new setup boasts a local cache situated on the physical host, with containers and jobs granted direct read-only access through an internal handshake mechanism.
• Deprecation of the Legacy Layer: We can disable EdenFS's rocksdb caches.
• Memory Footprint: We can also disable EdenFS's in-memory caches for SCM on RE by utilising the LMDB as the main in-memory cache, which is essential for efficiently collocating multiple workers on a single host.