1. Wiped-node back-fill (live gate check 4). Fixed upstream in
ZB.MOM.WW.LocalDb 0.1.2 and pinned here. The gate's diagnosis was slightly
off: the oplog cap was not the gate. Snapshot detection measured the peer's
gap against the oldest surviving oplog row and read an empty oplog as "no
gap possible" — and an empty oplog is the steady state of a converged pair,
since ack-pruning deletes everything the peer confirmed. The healthy state
was the one state that could not heal a wiped peer. Now measured against
last_acked_seq when the oplog is empty.
Pinned at this level too, not just the library's: the pair harness grows a
WipePassiveAsync (a NEW database — a rebuilt node comes back with a new node
id and a zero watermark), and the new scenario asserts the emptied oplog as
its precondition before wiping, then requires the deployment artifact to
come back byte-identical with no new deploy. Verified RED against the pinned
0.1.1 (times out waiting for back-fill) and green on 0.1.2.
2. Oplog growth on default-OFF nodes (live gate check 8), fixed at the source:
StoreAsync now skips entirely when the pointer already names this
deployment/revision, the SHA matches the bytes, and the expected chunk count
is present. Re-caching an artifact the node already holds — every restart's
boot-from-cache, every RestoreApplied — writes nothing and mints no oplog
rows, where before it cost a delete plus an insert per chunk plus a pointer
update, all identical to what was already there.
Identity is over the bytes and the chunks are counted, both deliberately: a
re-composed artifact can carry the same ids with different bytes, and a
pointer can name a deployment whose chunks are missing, where skipping would
make an unreadable cache permanent. Both guards verified RED against a naive
pointer-only skip.
The gate's stated bound was also wrong and is corrected in the doc: growth
was never headed for the 1M row cap. AddZbLocalDbReplication is registered
unconditionally, so MaintenanceBackgroundService runs on default-OFF nodes
and the 7-day MaxOplogAge cap prunes.
Runtime.Tests 412/0/31, Host.IntegrationTests LocalDb 45/45. Pre-existing and
unrelated: AbCip_Green_AgainstSim (needs the AB CIP docker fixture, red on a
clean master too) and a flaky Roslyn race test (green 2/2 in isolation).
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
Joseph Doherty
232bff5df7