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).
Concurrency hazards, DI lifetime hygiene, and one verify-only confirmation
across 8 modules. Highlights:
Concurrency:
- CentralUI-030: SandboxConsoleCapture writes routed through WriteSynchronized
locking on the captured StringWriter — intra-script Task fan-out can no
longer corrupt the per-call buffer.
- Commons-021: ExternalCallResult.Response now backed by Lazy<dynamic?>
(ExecutionAndPublication) — no more benign double-parse race.
- CD-017: DeploymentManagerRepository.DeleteDeploymentRecordAsync now takes
an expected RowVersion and seeds entry.OriginalValues so EF emits
DELETE ... WHERE Id=@id AND RowVersion=@prior; stale RowVersion now
throws DbUpdateConcurrencyException instead of silent overwrite.
- Transport-009: AuditCorrelationContext.BundleImportId backed by
AsyncLocal<Guid?> so concurrent imports get per-logical-call isolation
(was a scoped instance shared via AuditService across runs).
DI / lifetime:
- AuditLog-003: All 3 AuditLog actor handlers switched to CreateAsyncScope
+ await using — async EF disposal no longer swallowed.
- AuditLog-007: INodeIdentityProvider resolution standardised on
GetRequiredService<>() (was mixed with GetService<>()).
- AuditLog-011: AddAuditLogHealthMetricsBridge guarded by sentinel
descriptor check — calling twice no longer double-registers the hosted
service.
Shutdown / supervision:
- SiteCallAudit-002: AkkaHostedService adds a CoordinatedShutdown
cluster-leave task (drain-site-call-audit-singleton) that issues a
bounded GracefulStop(10s) so failover waits for in-flight upserts.
Registration safety:
- NS-020: AkkaHostedService now guards NotificationForwarder S&F
registration with _notificationDeliveryHandlerRegistered + throws
InvalidOperationException on double-register to make the regression loud.
VERIFY-only closures:
- NotifOutbox-005: Confirmed already closed by CD-015 fix (ac96b83) —
NotificationOutboxRepository.InsertIfNotExistsAsync uses the same
raw-SQL IF NOT EXISTS + 2601/2627 swallow pattern; race eliminated.
5+ new regression tests (CentralUI sandbox WhenAll, ExternalCallResult
64-reader Barrier, AuditLog DI idempotency, RowVersion stale-throw,
SiteCallAudit-002 shutdown drain). Build clean; affected suites all green.
README regenerated: 65 open (was 75).
Comm-016: delete dead HandleConnectionStateChanged + _debugSubscriptions /
_inProgressDeployments tracking + ConnectionStateChanged message record.
Disconnect detection is owned by the transport layers (gRPC keepalive PING
~25s; Ask-timeout at CommunicationService). Updates the
Component-Communication.md design doc to make that explicit.
SnF-018: NotificationForwarder.DeliverAsync now discards a corrupt buffered
payload (Warning log + return true) instead of returning false and parking
the row — honoring the design's "notifications do not park" invariant.
DM-018: reconciliation no longer force-sets Enabled, preserving an
intentional Disabled state after central failover.
ESG-018: DeliverBufferedAsync (both ExternalSystemClient + DatabaseGateway)
catches JsonException and returns false, turning a corrupt buffered row
into a parked operation instead of a retry-forever poison message.
InboundAPI-022: register ActiveNodeGate as IActiveNodeGate in the Central
DI branch so standby-node gating is actually wired up in production.
NS-019: remove orphaned NotificationDeliveryService /
INotificationDeliveryService / NotificationResult; central notification
delivery now lives entirely in NotificationOutbox.
SEL-016: normalise From/To filters to UTC before ISO-string compare so
non-UTC DateTimeOffset clients no longer get spuriously excluded events.
TE-017: include Description on attributes/alarms and a HashableConnections
projection (protocol, endpoint JSON, failover count) in the revision hash
and DiffService; staleness detection now catches description-only and
connection-endpoint edits.
Transport-001 and Transport-002 (also High) remain Open — they're being
handled in a follow-up batch because both touch BundleImporter.cs and
must serialise.
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.
Re-applies the full 10-category checklist to every src/ project — including
first-time reviews of the four newer components (AuditLog, NotificationOutbox,
SiteCallAudit, Transport) — so the code-reviews/ index reflects today's
codebase rather than the 2026-05-16 baseline. 172 new Open findings (0
Critical, 18 High, 62 Medium, 92 Low); 481 findings total across 23 modules.
regen-readme.py now derives each module's Last reviewed + Commit from its
findings.md header instead of hard-coding 2026-05-16 / 9c60592, so future
single-module re-reviews show their own date in the Module Status table.
Resolves StoreAndForward-001, ExternalSystemGateway-001, NotificationService-001
— one systemic gap where buffered messages were persisted but never delivered,
and the active node never replicated its buffer to the standby.
Delivery handlers (ExternalSystemGateway-001 / NotificationService-001):
- AkkaHostedService registers delivery handlers for the ExternalSystem,
CachedDbWrite and Notification categories after StoreAndForwardService starts;
each resolves its scoped consumer in a fresh DI scope.
- ExternalSystemClient, DatabaseGateway and NotificationDeliveryService each
gain a DeliverBufferedAsync method: re-resolve the target and re-attempt
delivery, returning true/false/throwing per the transient-vs-permanent contract.
- EnqueueAsync gains an attemptImmediateDelivery flag; CachedCallAsync and
NotificationDeliveryService.SendAsync pass false (they already attempted
delivery themselves) so registering a handler does not dispatch twice.
Replication (StoreAndForward-001):
- ReplicationService is injected into StoreAndForwardService; a new BufferAsync
helper replicates every enqueue, and successful-retry removes and parks are
replicated too. Fire-and-forget, no-op when replication is disabled.
Tests: StoreAndForwardReplicationTests (Add/Remove/Park observed),
attemptImmediateDelivery behaviour, and DeliverBufferedAsync paths for each
consumer. Full solution builds; StoreAndForward/ExternalSystemGateway/
NotificationService suites green.
Establishes a per-module code review workflow under code-reviews/ and
records the 2026-05-16 baseline review (commit 9c60592): 241 findings
across all src/ modules (6 Critical, 46 High, 100 Medium, 89 Low).
This is the clean starting point for remediation work.
Joseph Doherty