FasterLogHistorizationOutbox.PeekBatchAsync held the state lock across the
FasterLog scan. Once a backlog's head ages out of FasterLog's in-memory
window (any multi-minute historian outage), GetNext reads pages from disk
synchronously, and the recorder's appends (which index under the same lock)
blocked on an Akka dispatcher thread once per drain pass, exactly during
outage recovery.
The peek now snapshots the head under the lock, scans unlocked, and re-takes
the lock only when it met undecodable records, to reconcile them with the
index in O(records scanned) and drop one still at the head (re-checked,
since an ack or drop-oldest may have moved it). A test seam pauses the scan
and proves an append completes meanwhile; wrapping the scan in the lock
again fails it.
Rebased from the unpushed remed/lane-H2 branch (originally authored 2026-10-22
in session_01Ub9hGmYLQvn9XETzw7CMsT) onto current master.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Every IHistorianValueWriter caught Exception and returned false, including
OperationCanceledException from the drain's own token. The recorder's guard
("a cancelled pass is not a tag failure") was therefore dead code: at shutdown
mid-pass each cancelled group could be booked as a consecutive failure and,
with a sibling that already wrote, tip a healthy tag toward quarantine.
SqlServer, QuestDb and Gateway writers now rethrow a cancellation of the
caller's token; a cancellation-shaped error on a live token is still an
ordinary failed write.
The Gateway writer relabelled a Local-kind timestamp as UTC instead of
converting it, so the same value could land at two different times on two
backends. Stamped samples now go through LiveWritePreparer (Local -> UTC,
non-finite doubles not sent, duplicate timestamps keep the first); unstamped
samples are still left for the gateway to stamp, in batch order.
Rebased from the unpushed remed/lane-H2 branch (originally authored 2026-10-22
in session_01Ub9hGmYLQvn9XETzw7CMsT) onto current master.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Clears CommentChecker findings in src/ (3,280 -> 209, the remainder being false
positives like PLC-5/IEEE-754/M0.0) by adding missing summaries/params/returns,
normalising inheritdoc usage, and removing Gitea/review tracking IDs while keeping
the rationale they annotated. Comment-only: comment-stripped sources are identical
to the parent commit.
- A DateTime.MinValue start or end on DeleteRawModified is refused
BadInvalidArgument before the backend.
- Tests: anonymous without the HistoryUpdate role denied (with it allowed),
UpdateTagAttributes enabling historization sets HistoryWrite, a throwing
updater is BadInternalError, the MinValue bounds case; corrected the
test helper's comment on how the SDK base seeds unadmitted slots.
- GatewayHistorianValueWriter remarks describe the recorder's real status
capture (and that it does not persist on the gateway).
Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
Serialize always writes v2 ("HV2\0" | ver 2 | id | tag | kind | payload | status u32 | ts).
TryDeserialize reads v2 by magic, falls back to the legacy exact-length layout (also when the
magic matches but v2 validation fails), else returns false - never throws.
FasterLogHistorizationOutbox: RecoverState and PeekBatchAsync both use TryDeserialize. An
unreadable record is indexed under a synthetic id (FIFO truncation passes it), skipped by peek,
counted once (UnreadableCount), and dropped by peek once it reaches the head so it can never
pin the outbox.
Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
Four continuous-historization types (IHistorizationOutbox, HistorizationOutboxEntry,
IHistorianValueWriter/HistorizationValue, HistorizationCommitMode) drifted into a
ZB.MOM.WW.OtOpcUa.Core.Abstractions.Historian sub-namespace while the other six files
in the same folder correctly use the root namespace. This violated decision #59's
flat-public-surface rule and left InterfaceIndependenceTests.AllPublicTypes_LiveInRootNamespace
red on master (pre-existing, predates round-2 remediation).
Move all four to the root namespace and drop/retarget the now-redundant
'using ...Core.Abstractions.Historian;' in the ~11 consumers. No behavioral change.
Verified: Core.Abstractions.Tests 129/129 (was 128/129), Runtime.Tests Historian+DI 72/72,
Gateway driver unit 102/102, full solution build 0 errors.
Adds <summary>/<param>/<returns>/<inheritdoc> where missing and removes
project bookkeeping IDs (task/tracking refs) from shipped code comments,
so the docs read cleanly and CommentChecker is quiet except for known
false positives (PLC/protocol terms, event/IEqualityComparer inheritdoc).
Doc/comment-only; no logic changed; solution builds clean.
Addresses T18 review: GatewayHistorianValueWriter is a DI singleton holding a gRPC
channel — make it IAsyncDisposable so the container closes the channel gracefully at
shutdown. Tighten the blank-OutboxPath warning to state startup will fail.
Claude-Session: https://claude.ai/code/session_012SDSQ3AcaXqPcBtDESBRii
Continuous-historization engine for non-Galaxy driver tags. Registers
interest with the per-node DependencyMuxActor for the historized refs and
taps the VirtualTagActor.DependencyValueChanged values the mux fans:
coerce to numeric -> append to the durable IHistorizationOutbox (crash
boundary) -> off-thread drain writes batches through IHistorianValueWriter
and acks (FIFO-truncates) on success, backing off (exponential, capped) on
failure. Non-numeric values are dropped + metered (SQL analog path is
numeric-only).
- New seam IHistorianValueWriter + HistorizationValue in Core.Abstractions
so Runtime stays free of the gRPC driver.
- GatewayHistorianValueWriter (driver) adapts IHistorianGatewayClient.
WriteLiveValues: HistorizationValue -> HistorianLiveValue proto, WriteAck
Success||Queued -> true; non-throwing (errors -> false for retry).
- Drain runs via PipeTo(Self) so the mailbox never blocks on the gateway
write; appends awaited on the actor thread to stay serialized.
Adaptation vs plan: the mux fans DependencyValueChanged (TagId/Value/
TimestampUtc, no quality), not DriverInstanceActor.AttributeValuePublished,
so values are recorded Good-quality (192) by the same convention the
scripted-alarm host uses.
Claude-Session: https://claude.ai/code/session_012SDSQ3AcaXqPcBtDESBRii
I-1: GatewayAlarmHistorianWriter no longer dead-letters events cancelled
mid-drain at shutdown. WriteBatchAsync short-circuits remaining events to
RetryPlease once cancellation is requested, and SendOneAsync catches
OperationCanceledException (when the token is cancelled) -> RetryPlease,
so in-flight events stay queued instead of being permanently dropped.
I-2: FasterLogHistorizationOutbox.Dispose now guards the awaited periodic
loop with a broad catch (Exception) after the OperationCanceledException
catch, so a non-Faster teardown fault (e.g. ObjectDisposedException) can
never escape Dispose.
M-1: GatewayTagProvisioner skips the empty EnsureTags round-trip when every
request is non-historizable (early return).
M-2: GatewayTagProvisioner handles plain shutdown cancellation quietly
(Debug, not Warning), counting the unsent batch as Failed, never throwing.
M-3/M-4: Added remove-last-entry (TailAddress truncation branch) and
FIFO implicit-ack (RemoveAsync acks up to and including the target)
durability tests, both reopen-and-survive.
M-5: Clarifying comment in RecoverState on the transient over-capacity
rebuild after a crash between append-commit and drop-truncation-commit.
Claude-Session: https://claude.ai/code/session_012SDSQ3AcaXqPcBtDESBRii
Joseph Doherty