After the earlier memory work, SQLite's live heap is bounded but process
RSS still climbed about 70 MiB/min, nearly all anonymous and outside the
Go runtime and outside SQLite's own accounting, without any SQLITE_NOMEM.
The cause is glibc: the SQLite C library allocates and frees millions of
small page-cache chunks from many threads, and glibc keeps each arena's
freed chunks resident. With arenas uncapped it creates up to eight per
core, so on a large host RSS grows with the core count.
Set MALLOC_ARENA_MAX=2 in the image to bound the retained memory. Writes
are already serialized, so the two-arena cap costs no throughput. Update
the README Memory section.
Model: opus-4-8
sneak