Version 10.0.0
Cache (Architecture Guide)
Data StructuresSource Location

Cache in WiredTiger is represented by the various shared data structures that make up in-memory Btrees and subordinate data structures.

Memory used to read in and write out the on-disk representations of Btrees is not cached, it only exists temporarily during the I/O operation and while the data is transferred to or from the on-disk format.

Internally, the current cache state is represented by the WT_CACHE structure, which contains various counters that drive statistics and information used for eviction.