RAII things - #759
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Aug 12, 2026
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| counter | baseline | HEAD |
|---|---|---|
| on-disk: pools created | 10, plus 180 cache reuses | 10 |
| on-disk: connections opened / closed | 100 / 0 | 100 / 100 |
| on-disk: connections live after the last drop | 100 | 0 |
| in-memory: pools created | 190 | 10 |
| in-memory: connections opened / closed | 1,900 / 1,900 | 100 / 100 |
| peak live connections | 290 | 10 |
Process-wide atomic counters for pool and connection events, a snapshot/since API, and an ignored census_workload test that builds and drops ten surfnets per phase and prints the movement. Nothing is connected yet; the counters read zero until a backend routes its pool construction and connections through them. Closes are counted by Drop on a connection wrapper around the r2d2 manager, because CustomizeConnection::on_release fires only for broken or reaped connections, not at pool drop, and undercounts.
SQLite pools now build through CountingSqliteManager, and the build sites
in get_or_create_shared_pool report creation and cache reuse.
census_workload, ten surfnets built and dropped per phase:
on-disk: pools 10 (+180 reuses), conns opened 100, closed 0,
100 still live after the last drop
in-memory: pools 190, conns opened 1,900, closed 1,900,
peak 190 live during one surfnet
Connections owned by the process-global SHARED_POOLS survive every
surfnet drop. The in-memory line prices the 19 isolated pools each
surfnet builds.
…ions Each surfnet now opens one StorageBackend from its database URL and mints all of its kv stores from it. The SQLite pool moves off the process-global SHARED_POOLS map onto the backend, so connections live exactly as long as the surfnet that opened them; the checkpoint-dedup set and the per-store shutdown fan-out fall away with it. PostgreSQL keeps its process-level pool cache behind the backend, where pooling actually amortizes a network connection. In-memory SQLite now shares one database per surfnet instead of building 19 isolated pools, matching the on-disk layout of distinct tables in one database. The counting manager remains the pool's connection type, so connection opens and closes stay counted; the census build-site hook is reconnected in the next commit.
SqliteBackend::open reports pool creation, and a new assertion test,
dropping_backend_closes_connections, fails if any connection opened by a
backend survives its drop.
census_workload, same workload as the baseline measurement two commits
back:
on-disk: pools 10, conns opened 100, closed 100, live 0
in-memory: pools 10, conns opened 100, closed 100, live 0
Ten dropped surfnets leave 100 connections live on the baseline and none
here; in-memory construction opens 190 connections per surfnet there and
10 here.
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