baraba/Baradb
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
84 Commits 2 Branches 0 Tags
4791434ceab0d3c212172a479c5ade1293f8291c
Commit Graph

9 Commits

Author SHA1 Message Date
dimgigov 4791434cea FV-2: Raft leader step-down on partition loss 
- Add heartbeatReceived variable tracking last term with heartbeat
- Add Heartbeat action: leader sends keep-alive; recipient steps down on higher term
- Add HeartbeatTimeout: follower starts election if no heartbeat in current term
- Add LeaderLeaseExpired: leader steps down if it loses quorum connectivity
- Add LeaderHasSelfHeartbeat invariant: every leader must have valid heartbeat
- raft.tla now models realistic partition behavior (38M states verified)
- Update CHANGELOG -> v1.2.0, VERSION -> 1.2.0, PLAN.md, README.md
 2026-05-07 21:48:03 +03:00
dimgigov f9e5169c3d FV-6: Liveness properties + fairness constraints 
- mvcc.tla: Add CommitProgress liveness (verified with WF_vars)
- raft/twopc/mvcc/gossip: Add Spec definitions with WF_vars(Next)
- gossip.tla: Fix LearnViaGossip strength-based filtering
  (prevents overwriting Dead/Suspect with weaker state)
- twopc.tla: Add DecideCommitAction/DecideAbortAction for SF fairness
- Update all .cfg files to use SPECIFICATION Spec
- Update CHANGELOG.md -> v1.1.0, VERSION -> 1.1.0, PLAN.md
 2026-05-07 21:21:22 +03:00
dimgigov 112ed4764d FV-7: MVCC write skew detection 
- mvcc.tla: Add NoWriteSkew invariant
- mvcc.tla: CommitTxn checks for circular read-write dependencies
- models/mvcc.cfg: Add NoWriteSkew to checked invariants
- Update PLAN.md, ANALYSIS.md, README.md
 2026-05-07 19:43:58 +03:00
dimgigov 39e07b542d FV-3, FV-4: 2PC coordinator crash/recovery + participant timeout 
- twopc.tla: Add coordinatorLog (persistent WAL for decisions)
- twopc.tla: Add CrashCoordinator action
- twopc.tla: Add RecoverCoordinator action (reads from coordinatorLog)
- twopc.tla: Add ParticipantTimeout (only if coordinatorLog = Nil)
- twopc.tla: Add RecoveryConsistency invariant
- models/twopc.cfg: Add RecoveryConsistency to checked invariants
- Update PLAN.md, ANALYSIS.md, README.md with new metrics
 2026-05-07 19:40:09 +03:00
dimgigov 54711d0190 FV-1, FV-13: Raft prevLogIndex/prevLogTerm + CI fix 
- raft.tla: Add HasCompatiblePrefix check (prevLogIndex/prevLogTerm)
- raft.tla: Add RejectAppendEntries action for follower rejection
- raft.tla: Add conflict truncation + commitIndex/matchIndex adjustment
- raft.tla: Restore LogMatching invariant
- raft.tla: Guard AppendEntry to prevent term gaps in leader log
- models/raft.cfg: Add LogMatching to checked invariants
- .github/workflows/ci.yml: Replace container with setup-java + cache
- run_all.sh: Use -workers auto and -XX:+UseParallelGC
- Update PLAN.md, PLAN_DONE.md, ANALYSIS.md, README.md
 2026-05-07 19:21:01 +03:00
dimgigov ce3b078979 docs: unified improvement plan for verification + software (53 tasks) 
Covers both TLA+ specs and Nim code:
- P1: Raft prevLogIndex/LogMatching, replication data transfer,
  sharding migration (14 tasks)
- P2: backup.tla, crossmodal.tla, recovery.tla + Nim tests (14 tasks)
- P3: Liveness properties, write skew, 2PC crash recovery (12 tasks)
- P4: CI fixes, symmetry reduction, missing tests, inter-module
  integration (13 tasks)

Ties verification improvements directly to code improvements.
 2026-05-07 18:39:59 +03:00
dimgigov e715454c4e docs(verify): add detailed improvement plan with 13 tasks across 4 priorities 
Covers Raft prevLogIndex fix, 2PC recovery, MVCC write skew,
liveness properties, backup.tla, crossmodal.tla, CI fixes,
symmetry reduction, and Apalache migration.
 2026-05-07 18:31:20 +03:00
dimgigov 19d0ff7366 feat(verify): expand formal verification to 7 specs, add versioning, CI integration 
Added 3 new TLA+ specs:
- gossip.tla — SWIM gossip membership & failure detection
- deadlock.tla — wait-for graph deadlock detection
- sharding.tla — consistent hashing shard assignment

Improved existing 4 specs:
- raft.tla: added CommittedIndexValid invariant
- twopc.tla: added CoordinatorConsistency, NoDecideWithoutConsensus,
  ParticipantStateValid; increased to MaxTxnId=3
- mvcc.tla: added CommittedMustStart, CommittedVersionsUnique
- replication.tla: added AppliedLteCurrent, SemiSyncQuorum

Infrastructure:
- VERSION file (1.0.0)
- CHANGELOG.md
- ANALYSIS.md (weak spots & improvement plan)
- run_all.sh script for batch TLC verification
- CI verify job in GitHub Actions
- Updated README with new specs and properties

Total: 7 specs, 26 invariants, 11.6M states checked, 0 errors
 2026-05-07 18:26:55 +03:00
dimgigov e73bfb450c feat: formal verification suite — TLA+ specs for Raft, 2PC, MVCC, Replication 
Verified with TLC model checker:
- Raft: 475k states, ElectionSafety + StateMachineSafety
- 2PC: 22k states, Atomicity + NoOrphanBlocks
- MVCC: 177k states, NoDirtyReads + ReadOwnWrites + WriteWriteConflict
- Replication: 3.6M states, MonotonicLsn + AcksRemovePending
 2026-05-07 15:57:33 +03:00