consensus, miner: stale block mining support (#17506)

* consensus, miner: stale block supporting

* consensus, miner: refactor seal signature

* cmd, consensus, eth: add miner noverify flag

* cmd, consensus, miner: polish
This commit is contained in:
gary rong
2018-08-28 21:59:05 +08:00
committed by Péter Szilágyi
parent 63352bf424
commit c1c003e4ff
16 changed files with 317 additions and 183 deletions

View File

@ -35,6 +35,11 @@ import (
"github.com/ethereum/go-ethereum/log"
)
const (
// staleThreshold is the maximum depth of the acceptable stale but valid ethash solution.
staleThreshold = 7
)
var (
errNoMiningWork = errors.New("no mining work available yet")
errInvalidSealResult = errors.New("invalid or stale proof-of-work solution")
@ -42,16 +47,21 @@ var (
// Seal implements consensus.Engine, attempting to find a nonce that satisfies
// the block's difficulty requirements.
func (ethash *Ethash) Seal(chain consensus.ChainReader, block *types.Block, stop <-chan struct{}) (*types.Block, error) {
func (ethash *Ethash) Seal(chain consensus.ChainReader, block *types.Block, results chan<- *types.Block, stop <-chan struct{}) error {
// If we're running a fake PoW, simply return a 0 nonce immediately
if ethash.config.PowMode == ModeFake || ethash.config.PowMode == ModeFullFake {
header := block.Header()
header.Nonce, header.MixDigest = types.BlockNonce{}, common.Hash{}
return block.WithSeal(header), nil
select {
case results <- block.WithSeal(header):
default:
log.Warn("Sealing result is not read by miner", "mode", "fake", "sealhash", ethash.SealHash(block.Header()))
}
return nil
}
// If we're running a shared PoW, delegate sealing to it
if ethash.shared != nil {
return ethash.shared.Seal(chain, block, stop)
return ethash.shared.Seal(chain, block, results, stop)
}
// Create a runner and the multiple search threads it directs
abort := make(chan struct{})
@ -62,7 +72,7 @@ func (ethash *Ethash) Seal(chain consensus.ChainReader, block *types.Block, stop
seed, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
if err != nil {
ethash.lock.Unlock()
return nil, err
return err
}
ethash.rand = rand.New(rand.NewSource(seed.Int64()))
}
@ -75,34 +85,45 @@ func (ethash *Ethash) Seal(chain consensus.ChainReader, block *types.Block, stop
}
// Push new work to remote sealer
if ethash.workCh != nil {
ethash.workCh <- block
ethash.workCh <- &sealTask{block: block, results: results}
}
var pend sync.WaitGroup
var (
pend sync.WaitGroup
locals = make(chan *types.Block)
)
for i := 0; i < threads; i++ {
pend.Add(1)
go func(id int, nonce uint64) {
defer pend.Done()
ethash.mine(block, id, nonce, abort, ethash.resultCh)
ethash.mine(block, id, nonce, abort, locals)
}(i, uint64(ethash.rand.Int63()))
}
// Wait until sealing is terminated or a nonce is found
var result *types.Block
select {
case <-stop:
// Outside abort, stop all miner threads
close(abort)
case result = <-ethash.resultCh:
// One of the threads found a block, abort all others
close(abort)
case <-ethash.update:
// Thread count was changed on user request, restart
close(abort)
go func() {
var result *types.Block
select {
case <-stop:
// Outside abort, stop all miner threads
close(abort)
case result = <-locals:
// One of the threads found a block, abort all others
select {
case results <- result:
default:
log.Warn("Sealing result is not read by miner", "mode", "local", "sealhash", ethash.SealHash(block.Header()))
}
close(abort)
case <-ethash.update:
// Thread count was changed on user request, restart
close(abort)
if err := ethash.Seal(chain, block, results, stop); err != nil {
log.Error("Failed to restart sealing after update", "err", err)
}
}
// Wait for all miners to terminate and return the block
pend.Wait()
return ethash.Seal(chain, block, stop)
}
// Wait for all miners to terminate and return the block
pend.Wait()
return result, nil
}()
return nil
}
// mine is the actual proof-of-work miner that searches for a nonce starting from
@ -165,11 +186,12 @@ search:
}
// remote is a standalone goroutine to handle remote mining related stuff.
func (ethash *Ethash) remote(notify []string) {
func (ethash *Ethash) remote(notify []string, noverify bool) {
var (
works = make(map[common.Hash]*types.Block)
rates = make(map[common.Hash]hashrate)
results chan<- *types.Block
currentBlock *types.Block
currentWork [3]string
@ -226,11 +248,15 @@ func (ethash *Ethash) remote(notify []string) {
// submitWork verifies the submitted pow solution, returning
// whether the solution was accepted or not (not can be both a bad pow as well as
// any other error, like no pending work or stale mining result).
submitWork := func(nonce types.BlockNonce, mixDigest common.Hash, hash common.Hash) bool {
submitWork := func(nonce types.BlockNonce, mixDigest common.Hash, sealhash common.Hash) bool {
if currentBlock == nil {
log.Error("Pending work without block", "sealhash", sealhash)
return false
}
// Make sure the work submitted is present
block := works[hash]
block := works[sealhash]
if block == nil {
log.Info("Work submitted but none pending", "hash", hash)
log.Warn("Work submitted but none pending", "sealhash", sealhash, "curnumber", currentBlock.NumberU64())
return false
}
// Verify the correctness of submitted result.
@ -239,26 +265,36 @@ func (ethash *Ethash) remote(notify []string) {
header.MixDigest = mixDigest
start := time.Now()
if err := ethash.verifySeal(nil, header, true); err != nil {
log.Warn("Invalid proof-of-work submitted", "hash", hash, "elapsed", time.Since(start), "err", err)
return false
if !noverify {
if err := ethash.verifySeal(nil, header, true); err != nil {
log.Warn("Invalid proof-of-work submitted", "sealhash", sealhash, "elapsed", time.Since(start), "err", err)
return false
}
}
// Make sure the result channel is created.
if ethash.resultCh == nil {
// Make sure the result channel is assigned.
if results == nil {
log.Warn("Ethash result channel is empty, submitted mining result is rejected")
return false
}
log.Trace("Verified correct proof-of-work", "hash", hash, "elapsed", time.Since(start))
log.Trace("Verified correct proof-of-work", "sealhash", sealhash, "elapsed", time.Since(start))
// Solutions seems to be valid, return to the miner and notify acceptance.
select {
case ethash.resultCh <- block.WithSeal(header):
delete(works, hash)
return true
default:
log.Info("Work submitted is stale", "hash", hash)
return false
solution := block.WithSeal(header)
// The submitted solution is within the scope of acceptance.
if solution.NumberU64()+staleThreshold > currentBlock.NumberU64() {
select {
case results <- solution:
log.Debug("Work submitted is acceptable", "number", solution.NumberU64(), "sealhash", sealhash, "hash", solution.Hash())
return true
default:
log.Warn("Sealing result is not read by miner", "mode", "remote", "sealhash", sealhash)
return false
}
}
// The submitted block is too old to accept, drop it.
log.Warn("Work submitted is too old", "number", solution.NumberU64(), "sealhash", sealhash, "hash", solution.Hash())
return false
}
ticker := time.NewTicker(5 * time.Second)
@ -266,14 +302,12 @@ func (ethash *Ethash) remote(notify []string) {
for {
select {
case block := <-ethash.workCh:
if currentBlock != nil && block.ParentHash() != currentBlock.ParentHash() {
// Start new round mining, throw out all previous work.
works = make(map[common.Hash]*types.Block)
}
case work := <-ethash.workCh:
// Update current work with new received block.
// Note same work can be past twice, happens when changing CPU threads.
makeWork(block)
results = work.results
makeWork(work.block)
// Notify and requested URLs of the new work availability
notifyWork()
@ -315,6 +349,14 @@ func (ethash *Ethash) remote(notify []string) {
delete(rates, id)
}
}
// Clear stale pending blocks
if currentBlock != nil {
for hash, block := range works {
if block.NumberU64()+staleThreshold <= currentBlock.NumberU64() {
delete(works, hash)
}
}
}
case errc := <-ethash.exitCh:
// Exit remote loop if ethash is closed and return relevant error.