extract candidates logic, refactor update backend
This commit is contained in:
Felipe Andrade
parent
7405b8b360
commit
8436728419
@ -57,6 +57,10 @@ type backendState struct {
|
||||
bannedUntil time.Time
|
||||
}
|
||||
|
||||
func (bs backendState) IsBanned() bool {
|
||||
return time.Now().Before(bs.bannedUntil)
|
||||
}
|
||||
|
||||
// GetConsensusGroup returns the backend members that are agreeing in a consensus
|
||||
func (cp *ConsensusPoller) GetConsensusGroup() []*Backend {
|
||||
defer cp.consensusGroupMux.Unlock()
|
||||
@ -242,10 +246,10 @@ func NewConsensusPoller(bg *BackendGroup, opts ...ConsensusOpt) *ConsensusPoller
|
||||
|
||||
// UpdateBackend refreshes the consensus state of a single backend
|
||||
func (cp *ConsensusPoller) UpdateBackend(ctx context.Context, be *Backend) {
|
||||
banned := cp.IsBanned(be)
|
||||
RecordConsensusBackendBanned(be, banned)
|
||||
bs := cp.getBackendState(be)
|
||||
RecordConsensusBackendBanned(be, bs.IsBanned())
|
||||
|
||||
if banned {
|
||||
if bs.IsBanned() {
|
||||
log.Debug("skipping backend - banned", "backend", be.Name)
|
||||
return
|
||||
}
|
||||
@ -287,36 +291,19 @@ func (cp *ConsensusPoller) UpdateBackend(ctx context.Context, be *Backend) {
|
||||
log.Warn("error updating backend - finalized block", "name", be.Name, "err", err)
|
||||
}
|
||||
|
||||
bs := cp.getBackendState(be)
|
||||
oldFinalized := bs.finalizedBlockNumber
|
||||
oldSafe := bs.safeBlockNumber
|
||||
|
||||
expectedBlockTags := cp.checkExpectedBlockTags(
|
||||
finalizedBlockNumber, oldFinalized,
|
||||
safeBlockNumber, oldSafe,
|
||||
latestBlockNumber)
|
||||
updateDelay := time.Since(bs.lastUpdate)
|
||||
RecordConsensusBackendUpdateDelay(be, updateDelay)
|
||||
|
||||
changed, updateDelay := cp.setBackendState(be, peerCount, inSync,
|
||||
changed := cp.setBackendState(be, peerCount, inSync,
|
||||
latestBlockNumber, latestBlockHash,
|
||||
finalizedBlockNumber, safeBlockNumber)
|
||||
|
||||
RecordBackendLatestBlock(be, latestBlockNumber)
|
||||
RecordBackendSafeBlock(be, safeBlockNumber)
|
||||
RecordBackendFinalizedBlock(be, finalizedBlockNumber)
|
||||
RecordBackendUnexpectedBlockTags(be, !expectedBlockTags)
|
||||
RecordConsensusBackendUpdateDelay(be, updateDelay)
|
||||
|
||||
if !expectedBlockTags {
|
||||
log.Warn("backend banned - unexpected block tags",
|
||||
"backend", be.Name,
|
||||
"oldFinalized", oldFinalized,
|
||||
"finalizedBlockNumber", finalizedBlockNumber,
|
||||
"oldSafe", oldSafe,
|
||||
"safeBlockNumber", safeBlockNumber,
|
||||
"latestBlockNumber", latestBlockNumber,
|
||||
)
|
||||
cp.Ban(be)
|
||||
}
|
||||
|
||||
if changed {
|
||||
log.Debug("backend state updated",
|
||||
@ -329,6 +316,26 @@ func (cp *ConsensusPoller) UpdateBackend(ctx context.Context, be *Backend) {
|
||||
"safeBlockNumber", safeBlockNumber,
|
||||
"updateDelay", updateDelay)
|
||||
}
|
||||
|
||||
// sanity check for latest, safe and finalized block tags
|
||||
expectedBlockTags := cp.checkExpectedBlockTags(
|
||||
finalizedBlockNumber, oldFinalized,
|
||||
safeBlockNumber, oldSafe,
|
||||
latestBlockNumber)
|
||||
|
||||
RecordBackendUnexpectedBlockTags(be, !expectedBlockTags)
|
||||
|
||||
if !expectedBlockTags {
|
||||
log.Warn("backend banned - unexpected block tags",
|
||||
"backend", be.Name,
|
||||
"oldFinalized", oldFinalized,
|
||||
"finalizedBlockNumber", finalizedBlockNumber,
|
||||
"oldSafe", oldSafe,
|
||||
"safeBlockNumber", safeBlockNumber,
|
||||
"latestBlockNumber", latestBlockNumber,
|
||||
)
|
||||
cp.Ban(be)
|
||||
}
|
||||
}
|
||||
|
||||
// checkExpectedBlockTags for unexpected conditions on block tags
|
||||
@ -349,101 +356,41 @@ func (cp *ConsensusPoller) UpdateBackendGroupConsensus(ctx context.Context) {
|
||||
// get the latest block number from the tracker
|
||||
currentConsensusBlockNumber := cp.GetLatestBlockNumber()
|
||||
|
||||
// find out what backends are the candidates to be in the consensus group
|
||||
// and create a copy of current their state
|
||||
//
|
||||
// a serving node needs to be:
|
||||
// - not banned
|
||||
// - healthy (network latency and error rate)
|
||||
// - with minimum peer count
|
||||
// - in sync
|
||||
// - updated recently
|
||||
// - not lagging latest block
|
||||
// get the candidates for the consensus group
|
||||
candidates := cp.getConsensusCandidates()
|
||||
|
||||
candidates := make(map[*Backend]*backendState, len(cp.backendGroup.Backends))
|
||||
filteredBackendsNames := make([]string, 0, len(cp.backendGroup.Backends))
|
||||
for _, be := range cp.backendGroup.Backends {
|
||||
bs := cp.getBackendState(be)
|
||||
passed := true
|
||||
if time.Now().Before(bs.bannedUntil) {
|
||||
passed = false
|
||||
}
|
||||
if !be.IsHealthy() {
|
||||
passed = false
|
||||
}
|
||||
if !be.skipPeerCountCheck && bs.peerCount < cp.minPeerCount {
|
||||
passed = false
|
||||
}
|
||||
if !bs.inSync {
|
||||
passed = false
|
||||
}
|
||||
if bs.lastUpdate.Add(cp.maxUpdateThreshold).Before(time.Now()) {
|
||||
passed = false
|
||||
}
|
||||
if passed {
|
||||
candidates[be] = bs
|
||||
} else {
|
||||
filteredBackendsNames = append(filteredBackendsNames, be.Name)
|
||||
}
|
||||
}
|
||||
|
||||
// find the highest block, in order to use it defining the highest non-lagging ancestor block
|
||||
var highestLatestBlock hexutil.Uint64
|
||||
for _, bs := range candidates {
|
||||
if bs.latestBlockNumber > highestLatestBlock {
|
||||
highestLatestBlock = bs.latestBlockNumber
|
||||
}
|
||||
}
|
||||
|
||||
// find the highest common ancestor block
|
||||
// update the lowest latest block number and hash
|
||||
// the lowest safe block number
|
||||
// the lowest finalized block number
|
||||
var lowestLatestBlock hexutil.Uint64
|
||||
var lowestLatestBlockHash string
|
||||
var lowestFinalizedBlock hexutil.Uint64
|
||||
var lowestSafeBlock hexutil.Uint64
|
||||
lagging := make([]*Backend, 0, len(candidates))
|
||||
for be, bs := range candidates {
|
||||
// check if backend is lagging behind the highest block
|
||||
if bs.latestBlockNumber < highestLatestBlock && uint64(highestLatestBlock-bs.latestBlockNumber) > cp.maxBlockLag {
|
||||
lagging = append(lagging, be)
|
||||
continue
|
||||
}
|
||||
|
||||
// update the lowest common ancestor block
|
||||
for _, bs := range candidates {
|
||||
if lowestLatestBlock == 0 || bs.latestBlockNumber < lowestLatestBlock {
|
||||
lowestLatestBlock = bs.latestBlockNumber
|
||||
lowestLatestBlockHash = bs.latestBlockHash
|
||||
}
|
||||
|
||||
// update the lowest finalized block
|
||||
if lowestFinalizedBlock == 0 || bs.finalizedBlockNumber < lowestFinalizedBlock {
|
||||
lowestFinalizedBlock = bs.finalizedBlockNumber
|
||||
}
|
||||
|
||||
// update the lowest safe block
|
||||
if lowestSafeBlock == 0 || bs.safeBlockNumber < lowestSafeBlock {
|
||||
lowestSafeBlock = bs.safeBlockNumber
|
||||
}
|
||||
}
|
||||
|
||||
// remove lagging backends from the candidates
|
||||
for _, be := range lagging {
|
||||
filteredBackendsNames = append(filteredBackendsNames, be.Name)
|
||||
delete(candidates, be)
|
||||
}
|
||||
|
||||
// find the proposed block among the candidates
|
||||
// the proposed block needs have the same hash in the entire consensus group
|
||||
proposedBlock := lowestLatestBlock
|
||||
proposedBlockHash := lowestLatestBlockHash
|
||||
hasConsensus := false
|
||||
broken := false
|
||||
|
||||
if lowestLatestBlock > currentConsensusBlockNumber {
|
||||
log.Debug("validating consensus on block", "lowestLatestBlock", lowestLatestBlock)
|
||||
}
|
||||
|
||||
// if there is no block to propose, the consensus is automatically broken
|
||||
// this can happen when backends have just recovered
|
||||
broken := proposedBlock == 0 && currentConsensusBlockNumber > 0
|
||||
|
||||
// if there is a block to propose, check if it is the same in all backends
|
||||
if proposedBlock > 0 {
|
||||
for !hasConsensus {
|
||||
allAgreed := true
|
||||
@ -459,7 +406,12 @@ func (cp *ConsensusPoller) UpdateBackendGroupConsensus(ctx context.Context) {
|
||||
blocksDontMatch := (actualBlockNumber != proposedBlock) || (actualBlockHash != proposedBlockHash)
|
||||
if blocksDontMatch {
|
||||
if currentConsensusBlockNumber >= actualBlockNumber {
|
||||
log.Warn("backend broke consensus", "name", be.Name, "blockNum", actualBlockNumber, "proposedBlockNum", proposedBlock, "blockHash", actualBlockHash, "proposedBlockHash", proposedBlockHash)
|
||||
log.Warn("backend broke consensus",
|
||||
"name", be.Name,
|
||||
"actualBlockNumber", actualBlockNumber,
|
||||
"actualBlockHash", actualBlockHash,
|
||||
"proposedBlock", proposedBlock,
|
||||
"proposedBlockHash", proposedBlockHash)
|
||||
broken = true
|
||||
}
|
||||
allAgreed = false
|
||||
@ -488,6 +440,7 @@ func (cp *ConsensusPoller) UpdateBackendGroupConsensus(ctx context.Context) {
|
||||
"proposedBlockHash", proposedBlockHash)
|
||||
}
|
||||
|
||||
// update tracker
|
||||
cp.tracker.SetLatestBlockNumber(proposedBlock)
|
||||
cp.tracker.SetSafeBlockNumber(lowestSafeBlock)
|
||||
cp.tracker.SetFinalizedBlockNumber(lowestFinalizedBlock)
|
||||
@ -495,10 +448,17 @@ func (cp *ConsensusPoller) UpdateBackendGroupConsensus(ctx context.Context) {
|
||||
// update consensus group
|
||||
group := make([]*Backend, 0, len(candidates))
|
||||
consensusBackendsNames := make([]string, 0, len(candidates))
|
||||
for be, _ := range candidates {
|
||||
group = append(group, be)
|
||||
consensusBackendsNames = append(consensusBackendsNames, be.Name)
|
||||
filteredBackendsNames := make([]string, 0, len(cp.backendGroup.Backends))
|
||||
for _, be := range cp.backendGroup.Backends {
|
||||
_, exist := candidates[be]
|
||||
if exist {
|
||||
group = append(group, be)
|
||||
consensusBackendsNames = append(consensusBackendsNames, be.Name)
|
||||
} else {
|
||||
filteredBackendsNames = append(filteredBackendsNames, be.Name)
|
||||
}
|
||||
}
|
||||
|
||||
cp.consensusGroupMux.Lock()
|
||||
cp.consensusGroup = group
|
||||
cp.consensusGroupMux.Unlock()
|
||||
@ -522,7 +482,7 @@ func (cp *ConsensusPoller) IsBanned(be *Backend) bool {
|
||||
bs := cp.backendState[be]
|
||||
defer bs.backendStateMux.Unlock()
|
||||
bs.backendStateMux.Lock()
|
||||
return time.Now().Before(bs.bannedUntil)
|
||||
return bs.IsBanned()
|
||||
}
|
||||
|
||||
// Ban bans a specific backend
|
||||
@ -531,6 +491,9 @@ func (cp *ConsensusPoller) Ban(be *Backend) {
|
||||
defer bs.backendStateMux.Unlock()
|
||||
bs.backendStateMux.Lock()
|
||||
bs.bannedUntil = time.Now().Add(cp.banPeriod)
|
||||
|
||||
// when we ban a node, we give it the chance to start from any block when it is back
|
||||
bs.latestBlockNumber = 0
|
||||
bs.safeBlockNumber = 0
|
||||
bs.finalizedBlockNumber = 0
|
||||
}
|
||||
@ -613,12 +576,12 @@ func (cp *ConsensusPoller) isInSync(ctx context.Context, be *Backend) (result bo
|
||||
return res, nil
|
||||
}
|
||||
|
||||
// getBackendState creates a copy of backend state so that the caller can use it without locking
|
||||
func (cp *ConsensusPoller) getBackendState(be *Backend) *backendState {
|
||||
bs := cp.backendState[be]
|
||||
defer bs.backendStateMux.Unlock()
|
||||
bs.backendStateMux.Lock()
|
||||
|
||||
// we return a copy so that the caller can use it without locking
|
||||
return &backendState{
|
||||
latestBlockNumber: bs.latestBlockNumber,
|
||||
latestBlockHash: bs.latestBlockHash,
|
||||
@ -634,18 +597,76 @@ func (cp *ConsensusPoller) getBackendState(be *Backend) *backendState {
|
||||
func (cp *ConsensusPoller) setBackendState(be *Backend, peerCount uint64, inSync bool,
|
||||
latestBlockNumber hexutil.Uint64, latestBlockHash string,
|
||||
finalizedBlockNumber hexutil.Uint64,
|
||||
safeBlockNumber hexutil.Uint64) (changed bool, updateDelay time.Duration) {
|
||||
safeBlockNumber hexutil.Uint64) bool {
|
||||
bs := cp.backendState[be]
|
||||
bs.backendStateMux.Lock()
|
||||
changed = bs.latestBlockHash != latestBlockHash
|
||||
changed := bs.latestBlockHash != latestBlockHash
|
||||
bs.peerCount = peerCount
|
||||
bs.inSync = inSync
|
||||
bs.latestBlockNumber = latestBlockNumber
|
||||
bs.latestBlockHash = latestBlockHash
|
||||
bs.finalizedBlockNumber = finalizedBlockNumber
|
||||
bs.safeBlockNumber = safeBlockNumber
|
||||
updateDelay = time.Since(bs.lastUpdate)
|
||||
bs.lastUpdate = time.Now()
|
||||
bs.backendStateMux.Unlock()
|
||||
return
|
||||
return changed
|
||||
}
|
||||
|
||||
// getConsensusCandidates find out what backends are the candidates to be in the consensus group
|
||||
// and create a copy of current their state
|
||||
//
|
||||
// a candidate is a serving node within the following conditions:
|
||||
// - not banned
|
||||
// - healthy (network latency and error rate)
|
||||
// - with minimum peer count
|
||||
// - in sync
|
||||
// - updated recently
|
||||
// - not lagging latest block
|
||||
func (cp *ConsensusPoller) getConsensusCandidates() map[*Backend]*backendState {
|
||||
candidates := make(map[*Backend]*backendState, len(cp.backendGroup.Backends))
|
||||
|
||||
for _, be := range cp.backendGroup.Backends {
|
||||
bs := cp.getBackendState(be)
|
||||
if bs.IsBanned() {
|
||||
continue
|
||||
}
|
||||
if !be.IsHealthy() {
|
||||
continue
|
||||
}
|
||||
if !be.skipPeerCountCheck && bs.peerCount < cp.minPeerCount {
|
||||
continue
|
||||
}
|
||||
if !bs.inSync {
|
||||
continue
|
||||
}
|
||||
if bs.lastUpdate.Add(cp.maxUpdateThreshold).Before(time.Now()) {
|
||||
continue
|
||||
}
|
||||
|
||||
candidates[be] = bs
|
||||
}
|
||||
|
||||
// find the highest block, in order to use it defining the highest non-lagging ancestor block
|
||||
var highestLatestBlock hexutil.Uint64
|
||||
for _, bs := range candidates {
|
||||
if bs.latestBlockNumber > highestLatestBlock {
|
||||
highestLatestBlock = bs.latestBlockNumber
|
||||
}
|
||||
}
|
||||
|
||||
// find the highest common ancestor block
|
||||
lagging := make([]*Backend, 0, len(candidates))
|
||||
for be, bs := range candidates {
|
||||
// check if backend is lagging behind the highest block
|
||||
if bs.latestBlockNumber < highestLatestBlock && uint64(highestLatestBlock-bs.latestBlockNumber) > cp.maxBlockLag {
|
||||
lagging = append(lagging, be)
|
||||
}
|
||||
}
|
||||
|
||||
// remove lagging backends from the candidates
|
||||
for _, be := range lagging {
|
||||
delete(candidates, be)
|
||||
}
|
||||
|
||||
return candidates
|
||||
}
|
||||
|
||||
@ -428,7 +428,7 @@ func TestConsensus(t *testing.T) {
|
||||
require.Equal(t, "0xb1", bg.Consensus.GetSafeBlockNumber().String())
|
||||
})
|
||||
|
||||
t.Run("latest dropped below safe, and stayed inconsistent after ban", func(t *testing.T) {
|
||||
t.Run("latest dropped below safe, and stayed inconsistent", func(t *testing.T) {
|
||||
reset()
|
||||
useOnlyNode1()
|
||||
overrideBlock("node1", "latest", "0xd1")
|
||||
|
||||
Loading…
Reference in New Issue
Block a user