glm-5.3-flash
5eea656295
Post-convergence engine studies against the ADR-003 kv pin, using POC #3's harness unchanged (sqlite/fs arms byte-identical) plus the concurrency axis POC #3 never measured: - #5 postgres (B1-B6): solo pg floor ~1 ms (fsync-dominated, strace- decomposed), ~40x storage overhead; decisive scale-out — pg PUTs ~12x at 12 conns / ~37k ops/s while sqlite flatlines at its ~1.2k WAL single-writer ceiling. Viable future ADR for the multi-client replicator shape; durability/ops posture change, not a drop-in. - #6 redb (C1-C6): the "2-7x over sqlite" folklore inverted — sqlite ~430x over redb at crash-consistent puts (redb Immediate = 1 fdatasync/commit, 8-30 ms on this disk; its None tier is not crash-consistent). Reads ~530k/s but irrelevant. Ruled out at a durability-tier mismatch: WAL-NORMAL's shipped tier is not expressible in redb 4.x's two-level API. - Net: sqlite's pin now has four-way triangulated evidence (fs vs sqlite #3, pg #5, redb #6, lineage citation); batched commits proven as the universal lever across all three engines. Code: /workspace/alkblobs-postgres-poc, /workspace/alkblobs-redb-poc (standalone crates per the POC placement convention; 14 inherited tests passing in each, clippy -D warnings + fmt clean). Verification: no src/ changes — docs only; both POC crates verified (test/clippy/fmt) with findings recorded above.