v.20.8Improvement

Slight Performance Improvement of Memory Table with Small Block Construction

Slightly better performance of Memory table if it was constructed from a huge number of very small blocks (that's unlikely). Author of the idea: Mark Papadakis. Closes #14043. #14056 (alexey-milovidov).
Improves the performance of the Memory table engine when constructed from a large number of very small blocks.

Why it matters

This feature addresses performance inefficiencies that occur when a Memory table is built from many small blocks, enhancing data ingestion speed and resource utilization in such rare scenarios.

How to use it

No explicit user action is required. The optimization is automatically applied when using the Memory table engine, particularly benefiting workloads involving numerous small data blocks.