Well-localised perf fixes across 8 modules.
Lock decoupling / SQL streaming:
- AuditLog-005: SqliteAuditWriter gains dedicated read-only _readConnection
(+ _readLock) backed by WAL journal mode. GetBacklogStatsAsync,
ReadPendingAsync, ReadPendingSinceAsync, ReadForwardedAsync no longer
contend with the hot-path INSERT lock — backlog probes on a 30s timer
can't stall the writer under multi-hundred-K Pending backlog.
- SEL-022: dropped Cache=Shared from SiteEventLogger's default connection
string (single-connection logger; mode was dormant config).
Memory / streaming:
- CLI-019: bundle export streams base64 in 1 MB-aligned chunks via
Convert.TryFromBase64Chars straight into the FileStream — no more
full-bundle byte[] allocation.
- CentralUI-031: TransportImport now stages the upload to a per-session
temp file under Path.GetTempPath() (replaces in-memory byte[] field);
page implements IDisposable to delete the temp file on reset / new
upload / dispose. Per-circuit working set drops from ~100 MB to ~80 KB.
N+1 hoisting:
- Transport-008: added ITemplateEngineRepository.GetTemplatesWithChildrenAsync
bulk method; BundleImporter.PreviewAsync calls it once instead of per-
template-name. Single query with .Include(...).AsSplitQuery().
- DM-023: BuildDeployArtifactsCommandAsync's per-site loop now references
a pre-fetched GlobalArtifactSnapshot (shared scripts, external systems,
DB connections, notification lists, SMTP) instead of re-querying per site.
- MgmtSvc-023: HandleQueryDeployments unfiltered branch uses one
GetAllInstancesAsync bulk load + Dictionary<int,int?> lookup (was a
GetInstanceByIdAsync per record).
Small allocations / per-tick rebuilds:
- InboundAPI-019: AuditWriteMiddleware gates EnableBuffering() on
RequestHasBody() so GET/HEAD/DELETE/TRACE/OPTIONS and Content-Length:0
requests skip the FileBufferingReadStream allocation.
- NotifOutbox-006: ResolveAdapters dictionary now cached on
_adaptersCache (built lazily on first sweep) + actor-lifetime
_adaptersScope; ResolveAdapters no longer rebuilds per dispatch tick.
Verify-only:
- Comm-017: Confirmed _inProgressDeployments was deleted by Comm-016 in
commit ac96b83 — marked Resolved with that attribution. No code change.
Doc-correction:
- NS-022: Updated MailKitSmtpClientWrapper XML doc to spell out single-
connection / per-delivery-factory contract (option (b) — transient
client per Send — rejected because it re-handshakes TLS per email).
10+ new regression tests across 8 test projects. Build clean; affected
suites all green. README regenerated: 54 open (was 65).
NS-021/NO-001: thread FromAddress into XOAUTH2 so M365 stops rejecting
sends with 535 5.7.3. Added an additive oauth2UserName parameter on
ISmtpClientWrapper.AuthenticateAsync; both NotificationService and
NotificationOutbox now pass config.FromAddress.
NO-002: clamp non-positive SmtpConfiguration.MaxRetries/RetryDelay to the
1-min / 10-attempt fallback with a Warning so a misconfigured row no
longer parks transient failures on the first attempt or burn-loops.
NO-003: route a lifecycle-scoped CancellationToken from the
NotificationOutboxActor through the dispatch sweep into the adapter so
in-flight SMTP sends abort on PostStop instead of blocking
CoordinatedShutdown for the full SMTP timeout per row.
NO-004: await the central audit writer inside the existing try/catch
instead of fire-and-forget so the audit task can't outlive the per-sweep
DI scope and writer faults reach the operator log instead of being
silently dropped.
Two AuditLog integration tests seeded RetryDelay = TimeSpan.Zero to force
immediate re-claim on the second tick; updated them to 1 ms so they keep
the same intent without tripping the NO-002 clamp.
M4 Bundle B (B1) — add the central-only ICentralAuditWriter implementation
and inject it into NotificationOutboxActor so subsequent tasks (B2/B3) can
route attempt + terminal lifecycle events through the direct-write audit path.
- CentralAuditWriter: thin wrapper around IAuditLogRepository.InsertIfNotExistsAsync;
scope-per-call (matches AuditLogIngestActor / NotificationOutboxActor pattern);
stamps IngestedAtUtc; swallows all internal failures (alog.md §13).
- Registered as a singleton in AddAuditLog.
- NotificationOutboxActor ctor takes ICentralAuditWriter (validated non-null).
- Host wiring resolves the writer once from the root provider and passes it
into the singleton's Props.Create call.
- Existing TestKit fixtures updated with a NoOpCentralAuditWriter helper so
tests that don't exercise audit emission still compile and pass.
Joseph Doherty