Write Amplification Trade-offs in Tiered vs Leveled Compaction
Log-Structured Merge (LSM) trees optimize sequential write throughput by batching memory mutations into immutable MemTables before flushing sequentially to disk SSTable files.
Selecting between tiered compaction (which minimizes write amplification for ingest-heavy workloads) and leveled compaction (which optimizes point lookups and space reclamation) defines modern SSD durability.
Direct I/O Bypass and Kernel Polling Topologies
Integrating LSM engines with io_uring direct I/O bypasses the operating system page cache, achieving sub-10 microsecond read/write latencies on modern PCIe 5.0 NVMe storage hardware.