Module replication Future

Replication Module - Future Enhancements

Scope

• hardening and refinement of replication runtime behavior
• deterministic reliability improvements for failover/conflict/CDC paths
• stronger benchmark-backed guardrails for replication hot paths

Design Constraints

• replication contracts remain backward compatible within major release line.
• promotion/failover outcomes remain explicit and deterministic.
• conflict-resolution behavior remains strategy-bounded and observable.
• lag/degradation states remain visible and diagnosable.

Required Interfaces

Interface	Requirement
orchestration interfaces	deterministic init/replicate/promote semantics
propagation interfaces	stable WAL/logical slot and event stream behavior
conflict interfaces	deterministic resolver outcomes with explicit conflicts
observability interfaces	actionable lag/health/topology diagnostics

Implementation Notes

• tighten parity between failover transitions and health/lag diagnostics.
• standardize diagnostics for conflict, slot, and CDC incident classes.
• expand resilience tests for prolonged lag and replication bursts.
• broaden benchmark depth for multi-tier and multi-writer replication paths.

Implementation Baseline Evidence (as of 2026-07-19)

Doxygen Documentation Enhancements

• Comprehensive API documentation added to ReplicationManager public methods

  • initialize(), shutdown(), replicate(), waitForReplication()
  • addReplica(), removeReplica(), addWitnessNode()
  • triggerFailover(), promoteToLeader(), demoteToFollower()
  • Health check and observability methods properly documented

• Logical Replication Manager documentation completed

  • Slot lifecycle methods with lifecycle semantics
  • Change streaming API with buffer and LSN semantics
  • IReplicationListener callback semantics

Focused Test Evidence

• Conflict resolution test suite validates (17 total unit tests):
  • Three-Way Merge determinism and ancestor detection (RCS-01, 4 tests)
  • Field-Level Merge strategies (UNION, INTERSECT, LEFT_BIAS, RIGHT_BIAS) (RCS-02, 5 tests)
  • Context semantics (metadata, roles, client_ip, request_time) (RCS-03, 2 tests)
  • Idempotent and thread-safe resolver behavior (RCS-04, 2 tests)
  • Edge cases (minimal conflict sets, large conflict sets) (RCS-05, 2 tests)
  • Diagnostics consistency and strategy name observability (RCS-06, 2 tests)

Quality Baseline

• All replication module headers have @file Doxygen metadata
• 100% coverage of public API documentation
• Documentation enforcement applied per project guidelines
• Test infrastructure auto-discovers focused conflict test

Test Strategy

• unit and integration suites for manager, slot, conflict, logical replication, and observability paths.
• regressions for promotion failures, slot faults, and conflict edge scenarios.
• deterministic stress runs for replication lag and backpressure workloads.
• release-profile benchmark runs for mapped replication targets.

Performance Targets

• replication hot paths remain inside regression budgets.
• promotion/conflict/CDC-sensitive operations remain stable at p95/p99 envelopes.
• mapped benchmark manifests reach no-missing-case status for release gating.

Security / Reliability

• maintain strict validation before replication state transitions.
• preserve explicit failure signaling for promotion, slot, and conflict faults.
• enforce bounded behavior under lag spikes and bursty replication traffic.
• keep diagnostics actionable for production replication incidents.

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