Overview: Gamma supports three storage types: RocksDB, MemoryOnly, and Mmap. v3.2.7 mainly modifies and optimizes Mmap. The specific modifications are as follows:

1.Use a unified way to store vectors and scalars; 2.Use cache to improve query performance; 3.Reduce scalar memory usage; 4.Supports dynamic modification of the cache size, and flexible storage and retraction of memory; 5.Fix the occasional inaccurate query of scalar index 6.Support raft snapshot