Variant B2 of the #78 benchmark: migration FlipAuditLogClusteredKey drops the
twelve non-clustered indexes, re-adds PK_AuditLog as (OccurredAtUtc, EventId)
on ps_AuditLog_Month, adds the aligned unique UX_AuditLog_EventId_Occurred
(EventId, OccurredAtUtc) for the idempotency probe, and rebuilds the twelve
indexes unchanged. Guarded (re-runnable) Up, inverse-rebuild Down; production
scripts docs/plans/sql/FlipAuditLogClusteredKey{,.rollback}.sql.
The partition-switch purge staging table now reads the live clustered key
order from sys.index_columns, so it switches either shape (old binaries
hard-code the old order: ship with the binaries, both centrals stopped).
Evidence: 300k rows, page 1 90,532 -> 34 logical reads (ordered backward
clustered scan under Top), keyset page 90,532 -> 46, probe 14 -> 14;
FlipAuditLogClusteredKeyMigrationTests pins indexes, grants, Down/Up, the
staging key (mutation: hard-coded old key fails SWITCH) and the read ratio.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Audit roadmap T2 (alog.md §15.2): with AuditLog:Archive:Enabled (default off)
the purge actor writes each expired monthly partition to Parquet under an
absolute AuditLog:Archive:Directory before switching it out, so audit rows
outlive RetentionDays.
- Parquet.Net 6.1.0 (fully managed; NuGetAudit clean) in central package
management.
- AuditArchiveParquet: data file = the ten stored columns, OccurredAtUtc as a
UTC microsecond timestamp plus exact OccurredAtUtcTicks, and ChainSeq/RowHash;
tombstone file = the month's per-channel purge tombstones. Buffered row
groups; the files are plain Parquet (DuckDB/pyarrow read them).
- AuditLogPartitionArchive (IAuditLogArchive): reads the partition's rows,
chain heads and tombstones in one transaction under the chain lock SHARED,
writes {Directory}/{YYYY}/auditlog-{YYYY-MM}-{stamp}Z.parquet,
.tombstones.parquet and a .manifest.json (counts, SHA-256 per file, each
month's head and prior anchor) via tmp + rename, manifest last. Archives are
never overwritten.
- Archive before purge: SwitchOutPartitionAsync gains an internal guarded
overload. Under the EXCLUSIVE chain lock it re-counts the partition and
re-reads each month's LastSeq and THROWs 51002/51003 (nothing purged) unless
both still equal the archive's, so the switch's checkpoint anchor is exactly
the archive's chain end. The manifest is then marked Purged.
- Fail closed: a partition that cannot be archived is not purged; the failure
takes the existing AuditLogPurgeFailedEvent / PurgeFailures path. Success
publishes AuditLogArchivedEvent.
- Verify: file hashes and counts against the manifest, the chain recomputed
from the archived rows and tombstones (AuditChainVerifier), and the chain end
against the database anchor (Matches / Superseded / NotPurged / Mismatch).
- AuditLogArchiveOptionsValidator: Directory required when enabled and must be
absolute; RowGroupSize, timeouts bounded.
No migration: the purger role already reads AuditLog, the head and tombstones.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Audit roadmap T1 (alog.md §11.4): one chain per UTC calendar month of
OccurredAtUtc. Each chained row carries ChainSeq (gap-free within its month)
and RowHash = SHA-256(prev.RowHash || canonical(row)); the v1 canonical form
(AuditChainHasher) is pinned by a known-answer vector computed independently.
- Migration AddAuditLogHashChain: nullable ChainSeq/RowHash on dbo.AuditLog
(metadata-only add), AuditLogChainHead (per-month chain end + partition-purge
checkpoint anchor), AuditLogChainTombstone, two partition-aligned filtered
indexes, scadabridge_audit_chainer role with a column-level UPDATE grant.
Production script docs/plans/sql/AddAuditLogHashChain.sql.
- AuditLogHashChain chains unchained rows oldest month first under an
exclusive sp_getapplock (zero timeout, so a dual-active central pair still
yields one chain), with an optimistic head check and a ChainSeq IS NULL
row-count check that roll a pass back instead of leaving a gap. The ingest
path is untouched.
- Purges keep the chain verifiable: the partition switch records the month's
checkpoint anchor and drops its tombstones; the per-channel DELETE writes a
tombstone per chained row in the same transaction (OUTPUT INTO). Both, and
the SourceNode backfill, hold the chain lock; the backfill skips chained
rows. The switch staging table gains the two new columns.
- AuditChainVerifier reports the first break (partition, ChainSeq, EventId,
kind) for edited, deleted, reordered rows and tail truncation.
- AuditLogHashChainService (central, default OFF via AuditLog:HashChain).
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Comment/XML-doc changes only, no code logic:
- strip project-tracking references (WP*, P*-*, row-NN, #NN, Task N) from
comments, keeping the explanatory rationale
- add missing summaries, <param>, <returns>, <typeparam> and <inheritdoc/>
- replace misused <inheritdoc/> with real docs; where <inheritdoc/> was
combined with useful remarks, move the rationale into // comments
- drop stale replicationActor <param> on DeploymentManagerActor ctor
Remaining 5 are false positives (CWE-1236 x2, failures-1, year-0001, M365).
Build 0 errors / 0 warnings.
Second slice of the 2026-09-09 whole-system review remediation
(docs/plans/2026-09-09-arch-review.md §10), on top of the High slice 146a1323.
Runtime/devices: SR-2 alarm on-trigger integration scope; SR-3 correlated NativeAlarmActor
subscribe retry; SR-4 immutable audited DB target; SR-5 ordered InstanceActor stop/flush;
SR-12 rehydration fence; SR-13 S&F gate recheck per delivery; DC-4 no OPC UA security
downgrade; DC-5 alarm snapshot for every new subscriber; ORCH-1 sync-dispose joins the pump.
Management/UI: MG-2 site scope on audit tree + Flow Debugger Replay; MG-3 stale-probe memo
removed; MG-4 server-owned bulk-deploy deadline; UI-5 sandbox runs in a killable child
process (new CentralUI.SandboxWorker project); UI-14 bounded sandbox output/IPC.
Edge/audit: EI-1 relay audit ownership; EI-2 SkipBodyCapture suppresses error text; EI-3/EI-11
error-field redaction + caps; EI-4 single relay deadline, pre-execution-only retry; EI-5
authenticated relay provenance; EI-10 body cap before audit read.
Persistence/contracts: DL-1 global Instance.UniqueName unique index + conflict translation;
DL-2 DataConnection protocol config encrypted at rest (migration
20260909203046_EnforceGlobalInstanceNamesAndProtectProtocolConfiguration — coordinated
central upgrade, old binaries cannot read protected rows); DL-3 bounded Replay paging;
DL-6 cross-site Overwrite of a deployed instance rejected; XC-4 proto descriptor contract test.
Config/hygiene: XC-1 central listener isolation by local port; XC-2/XC-3 inert SMTP + cron
keys removed from rig settings; CM-2 env2 bootstrap guard enabled; DC-6 deploy site exit code;
DC-7 notifier retries only explicit standby rejection; XC-5 ClusterClient purged from docs.
Gates recorded in the report: build 0/0, 9 397 passed / 0 failed, rig redeployed on all
eight nodes with the migration applied. 46 Low findings remain open.
GetTraceEventsAsync re-implemented GetExecutionTreeAsync's execution-chain walk
as a second copy: the upward ParentExecutionId climb, the root MIN(OccurredAtUtc)
window, and the recursive Edges/Chain CTE with its DISTINCT-edges trick and
MAXRECURSION cap. Two walkers that had to stay in step on window slack, depth and
the edge distillation.
Extracted into three shared members:
- ChainAnchor (root execution id + root's first event timestamp, with the
Edges window predicate derived from it)
- ResolveChainAnchorAsync — phase 1 up-walk plus the root window read
- ChainCtePrefix / AddChainParameters — the Edges/Chain CTE prefix and its
@root/@winStart/@winEnd binding
Each walker appends its own projection to the prefix: GetExecutionTreeAsync the
ChainIds CTE plus the per-execution aggregate, GetTraceEventsAsync the bare id
union. Both keep OPTION (MAXRECURSION 32).
Pure refactor. The tree walker's generated SQL is byte-identical (verified by
diffing the composed command text against the pre-change literal); the trace
walker's differs only by the SQL comment lines it now inherits from the shared
prefix. Behaviour is pinned by the existing MSSQL-backed tests
(GetExecutionTree_MultiLevelChain / _StubParentNode / _RespectsMaxRecursion,
ExecutionTree_Bounds_EdgeScan_To_Root_Window, and both
AuditLogRepositoryTraceEventsTests) — 410 passed / 0 skipped before and after.
Claude-Session: https://claude.ai/code/session_01NcMG6xXdsJbmD2wYAgkK29
GetTraceEventsAsync widens its channel filter to ScriptTrace ∪ ApiOutbound ∪
DbOutbound ∪ Notification ∪ (ApiInbound & InboundRequest) (plan D6); SecuredWrite,
Cluster and InboundAuthFailure rows in the same tree stay excluded. The site
SqliteAuditWriter.ReadByExecutionIdsAsync already had no channel predicate — pinned
by a test. Interface doc updated to match.
Claude-Session: https://claude.ai/code/session_01NcMG6xXdsJbmD2wYAgkK29
Flow Debugger (design 2026-09-05 §7.1): IAuditLogRepository.GetTraceEventsAsync walks any
entry id to its root and down the Edges/Chain CTE exactly as GetExecutionTreeAsync, then
returns the chain's ScriptTrace rows plus the ApiInbound.InboundRequest row via the canonical
row mapper, ordered (OccurredAtUtc, EventId). Test doubles implement the new member with a
NotSupported stub.
Claude-Session: https://claude.ai/code/session_01GSLkkHKz9JrAtmJjmQK3cP
Six adversarial-review findings in the central SQL/ingest layer.
F1 (AuditLogRepository.InsertChunkAsync) — the set-based ingest declared each
string parameter at its COLUMN width (Actor/Target 256, Action 64, Outcome 16,
Category 32, SourceNode 64), so SqlClient truncated an over-long value at bind
time and committed the mutilated row — silent, in an append-only store, with no
PayloadTruncated flag — while the per-row and reconciliation paths sent the same
value in full and let the server reject it with 2628. Bind at the value's own
length instead; explicit SqlDbType is kept (it fixes the VALUES constructor's
derived column types and datetime2 precision). Design: reject everywhere,
truncate nowhere — matching today's per-row behaviour.
F2 (SiteCallAuditRepository.UpsertAsync) — the single-statement upsert ran the
monotonic UPDATE first and INSERTed only if nothing matched. Two writers racing
the first packet of one TrackedOperationId (the cached dual-write and the
reconciliation pull carry DIFFERENT lifecycle states) both matched nothing, and
the loser then skipped its INSERT or swallowed a 2627 — dropping its
Status/RetryCount/HttpStatus/TerminalAtUtc. Legs swapped to
`IF NOT EXISTS … INSERT; UPDATE <monotonic>` — still one round trip, and the
loser's UPDATE now lands on the winner's row. The duplicate-key catch re-runs
the monotonic UPDATE for the same reason. Moved to raw SQL with explicitly-typed
parameters so the intricate rank predicate exists in exactly one place (an
untyped DateTime would bind as `datetime` and round the freshness tiebreaker).
F3 (docs/plans/sql/*.sql) — filtered-index DDL failed with error 1934 under the
documented `docker exec … sqlcmd` path, which defaults QUOTED_IDENTIFIER OFF;
once IX_Notifications_Delivered exists, QI-OFF DML on Notifications fails too.
All four scripts now open with `SET QUOTED_IDENTIFIER ON; SET ANSI_NULLS ON; GO`
(own batch, so it is in force when the next batch parses), and the migration
convention in Component-ConfigurationDatabase.md documents `sqlcmd -I`. Verified
live: the pre-fix script fails 1934 without -I, the fixed one applies.
F4 (SiteCallAuditActor) — the off-mailbox reconciliation/purge passes reuse the
injected repository, so tests drove one DbContext from the pass and a mailbox
handler concurrently. Serialized at the CALL via a private SerializedRepository
wrapper applied only by the test constructors, rather than running the pass
on-mailbox: production keeps its PipeTo shape untouched, and the existing
"a blocked drain does not stall ingest/query/KPI" regression tests stay
meaningful (they would have been invalidated by suspending the mailbox).
F5 (AuditLogIngestActor) — when the batch failed because the 20 s IngestBudget
expired, the per-row fallback reused the same expired token: N instant failures,
N counter bumps, zero accepted. The fallback now gets a fresh 5 s budget (inside
the 30 s outer Ask), and a blown budget bumps the failure counter ONCE for the
batch instead of once per row.
F6 (NotificationOutboxRepository.UpdateAsync) — ExecuteUpdate's row count was
discarded, so an operator Retry/Discard of a notification the retention purge had
already deleted reported success (the pre-ExecuteUpdate code threw
DbUpdateConcurrencyException). UpdateAsync now returns whether a row matched; the
operator one-shots answer "notification not found" and emit no audit row for the
action that did not happen, while the dispatcher logs a warning (its delivery
already happened; nothing to retry). GetByIdAsync switched to AsNoTracking since
the write is out-of-band.
Tests: 5 new SQL-backed regressions (over-long Target rejected on both paths +
boundary round-trip; concurrent first-write and already-created-by-another-writer
upserts; vanished-row UpdateAsync), a token-identity pin on the ingest fallback,
a repository-concurrency detector for the SiteCallAudit passes, and vanished-row
operator-path tests. The F1/F2/F4 regressions were each confirmed failing against
the pre-fix code. Suites: ConfigurationDatabase 369, AuditLog 378, SiteCallAudit
66, NotificationOutbox 152 — all green, solution builds with 0 warnings.
Installs SqlServerRetryingExecutionStrategy (5 retries, 30s cap) so transient SQL
faults retry transparently on every read-side path. Manual transactions aren't
auto-retried, so AuditLogIngestActor's idempotent dual-write is wrapped in an
explicit CreateExecutionStrategy().ExecuteAsync to become retriable. Verified
empirically that existing manual transactions (BundleImporter) are unaffected —
EF skips the strategy while a transaction is already active.
Remove project bookkeeping citations from shipped code comments across the
solution: hyphenated task IDs (WP-14, StoreAndForward-025), milestone/task/
issue refs (M3, Task 4, Audit Log #23, #21), Bundle X task-bundle labels,
and C/D/K/S/T phase labels.
Comment text only — no code logic, string/log literals, or XML-doc structure
changed. Genuine descriptions are preserved (only the citation is stripped),
and technical lookalikes are retained (UTF-8, SHA-256, T00:00:00, M365,
UTC-5, pre-C4/pre-C5 schema versions). Flagged by the new CommentChecker
TaskReferenceInComment / TrackingReferenceInComment checks plus targeted
grep passes; full solution builds clean, append-only guard tests pass.
Joseph Doherty