Merge pull request #16720 from rjl493456442/PreTxsEvent

all: collate new transaction events together

19 files changed, 172 insertions, 121 deletions

diff --git a/accounts/abi/bind/backends/simulated.go b/accounts/abi/bind/backends/simulated.go
index 7b605e1c1..fd69538d5 100644
--- a/accounts/abi/bind/backends/simulated.go
+++ b/accounts/abi/bind/backends/simulated.go
@@ -454,7 +454,7 @@ func (fb *filterBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*ty
 	return logs, nil
 }
 
-func (fb *filterBackend) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
+func (fb *filterBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
 	return event.NewSubscription(func(quit <-chan struct{}) error {
 		<-quit
 		return nil
diff --git a/core/events.go b/core/events.go
index 6f404f612..8d200f2a2 100644
--- a/core/events.go
+++ b/core/events.go
@@ -21,8 +21,8 @@ import (
 	"github.com/ethereum/go-ethereum/core/types"
 )
 
-// TxPreEvent is posted when a transaction enters the transaction pool.
-type TxPreEvent struct{ Tx *types.Transaction }
+// NewTxsEvent is posted when a batch of transactions enter the transaction pool.
+type NewTxsEvent struct{ Txs []*types.Transaction }
 
 // PendingLogsEvent is posted pre mining and notifies of pending logs.
 type PendingLogsEvent struct {
@@ -35,9 +35,6 @@ type PendingStateEvent struct{}
 // NewMinedBlockEvent is posted when a block has been imported.
 type NewMinedBlockEvent struct{ Block *types.Block }
 
-// RemovedTransactionEvent is posted when a reorg happens
-type RemovedTransactionEvent struct{ Txs types.Transactions }
-
 // RemovedLogsEvent is posted when a reorg happens
 type RemovedLogsEvent struct{ Logs []*types.Log }
 
diff --git a/core/tx_journal.go b/core/tx_journal.go
index e872d7b53..1397e9fd3 100644
--- a/core/tx_journal.go
+++ b/core/tx_journal.go
@@ -56,7 +56,7 @@ func newTxJournal(path string) *txJournal {
 
 // load parses a transaction journal dump from disk, loading its contents into
 // the specified pool.
-func (journal *txJournal) load(add func(*types.Transaction) error) error {
+func (journal *txJournal) load(add func([]*types.Transaction) []error) error {
 	// Skip the parsing if the journal file doens't exist at all
 	if _, err := os.Stat(journal.path); os.IsNotExist(err) {
 		return nil
@@ -76,7 +76,21 @@ func (journal *txJournal) load(add func(*types.Transaction) error) error {
 	stream := rlp.NewStream(input, 0)
 	total, dropped := 0, 0
 
-	var failure error
+	// Create a method to load a limited batch of transactions and bump the
+	// appropriate progress counters. Then use this method to load all the
+	// journalled transactions in small-ish batches.
+	loadBatch := func(txs types.Transactions) {
+		for _, err := range add(txs) {
+			if err != nil {
+				log.Debug("Failed to add journaled transaction", "err", err)
+				dropped++
+			}
+		}
+	}
+	var (
+		failure error
+		batch   types.Transactions
+	)
 	for {
 		// Parse the next transaction and terminate on error
 		tx := new(types.Transaction)
@@ -84,14 +98,17 @@ func (journal *txJournal) load(add func(*types.Transaction) error) error {
 			if err != io.EOF {
 				failure = err
 			}
+			if batch.Len() > 0 {
+				loadBatch(batch)
+			}
 			break
 		}
-		// Import the transaction and bump the appropriate progress counters
+		// New transaction parsed, queue up for later, import if threnshold is reached
 		total++
-		if err = add(tx); err != nil {
-			log.Debug("Failed to add journaled transaction", "err", err)
-			dropped++
-			continue
+
+		if batch = append(batch, tx); batch.Len() > 1024 {
+			loadBatch(batch)
+			batch = batch[:0]
 		}
 	}
 	log.Info("Loaded local transaction journal", "transactions", total, "dropped", dropped)
diff --git a/core/tx_pool.go b/core/tx_pool.go
index 388b40058..f89e11441 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -238,7 +238,7 @@ func NewTxPool(config TxPoolConfig, chainconfig *params.ChainConfig, chain block
 	if !config.NoLocals && config.Journal != "" {
 		pool.journal = newTxJournal(config.Journal)
 
-		if err := pool.journal.load(pool.AddLocal); err != nil {
+		if err := pool.journal.load(pool.AddLocals); err != nil {
 			log.Warn("Failed to load transaction journal", "err", err)
 		}
 		if err := pool.journal.rotate(pool.local()); err != nil {
@@ -444,9 +444,9 @@ func (pool *TxPool) Stop() {
 	log.Info("Transaction pool stopped")
 }
 
-// SubscribeTxPreEvent registers a subscription of TxPreEvent and
+// SubscribeNewTxsEvent registers a subscription of NewTxsEvent and
 // starts sending event to the given channel.
-func (pool *TxPool) SubscribeTxPreEvent(ch chan<- TxPreEvent) event.Subscription {
+func (pool *TxPool) SubscribeNewTxsEvent(ch chan<- NewTxsEvent) event.Subscription {
 	return pool.scope.Track(pool.txFeed.Subscribe(ch))
 }
 
@@ -653,7 +653,7 @@ func (pool *TxPool) add(tx *types.Transaction, local bool) (bool, error) {
 		log.Trace("Pooled new executable transaction", "hash", hash, "from", from, "to", tx.To())
 
 		// We've directly injected a replacement transaction, notify subsystems
-		go pool.txFeed.Send(TxPreEvent{tx})
+		go pool.txFeed.Send(NewTxsEvent{types.Transactions{tx}})
 
 		return old != nil, nil
 	}
@@ -712,10 +712,11 @@ func (pool *TxPool) journalTx(from common.Address, tx *types.Transaction) {
 	}
 }
 
-// promoteTx adds a transaction to the pending (processable) list of transactions.
+// promoteTx adds a transaction to the pending (processable) list of transactions
+// and returns whether it was inserted or an older was better.
 //
 // Note, this method assumes the pool lock is held!
-func (pool *TxPool) promoteTx(addr common.Address, hash common.Hash, tx *types.Transaction) {
+func (pool *TxPool) promoteTx(addr common.Address, hash common.Hash, tx *types.Transaction) bool {
 	// Try to insert the transaction into the pending queue
 	if pool.pending[addr] == nil {
 		pool.pending[addr] = newTxList(true)
@@ -729,7 +730,7 @@ func (pool *TxPool) promoteTx(addr common.Address, hash common.Hash, tx *types.T
 		pool.priced.Removed()
 
 		pendingDiscardCounter.Inc(1)
-		return
+		return false
 	}
 	// Otherwise discard any previous transaction and mark this
 	if old != nil {
@@ -747,7 +748,7 @@ func (pool *TxPool) promoteTx(addr common.Address, hash common.Hash, tx *types.T
 	pool.beats[addr] = time.Now()
 	pool.pendingState.SetNonce(addr, tx.Nonce()+1)
 
-	go pool.txFeed.Send(TxPreEvent{tx})
+	return true
 }
 
 // AddLocal enqueues a single transaction into the pool if it is valid, marking
@@ -907,6 +908,9 @@ func (pool *TxPool) removeTx(hash common.Hash, outofbound bool) {
 // future queue to the set of pending transactions. During this process, all
 // invalidated transactions (low nonce, low balance) are deleted.
 func (pool *TxPool) promoteExecutables(accounts []common.Address) {
+	// Track the promoted transactions to broadcast them at once
+	var promoted []*types.Transaction
+
 	// Gather all the accounts potentially needing updates
 	if accounts == nil {
 		accounts = make([]common.Address, 0, len(pool.queue))
@@ -939,8 +943,10 @@ func (pool *TxPool) promoteExecutables(accounts []common.Address) {
 		// Gather all executable transactions and promote them
 		for _, tx := range list.Ready(pool.pendingState.GetNonce(addr)) {
 			hash := tx.Hash()
-			log.Trace("Promoting queued transaction", "hash", hash)
-			pool.promoteTx(addr, hash, tx)
+			if pool.promoteTx(addr, hash, tx) {
+				log.Trace("Promoting queued transaction", "hash", hash)
+				promoted = append(promoted, tx)
+			}
 		}
 		// Drop all transactions over the allowed limit
 		if !pool.locals.contains(addr) {
@@ -957,6 +963,10 @@ func (pool *TxPool) promoteExecutables(accounts []common.Address) {
 			delete(pool.queue, addr)
 		}
 	}
+	// Notify subsystem for new promoted transactions.
+	if len(promoted) > 0 {
+		pool.txFeed.Send(NewTxsEvent{promoted})
+	}
 	// If the pending limit is overflown, start equalizing allowances
 	pending := uint64(0)
 	for _, list := range pool.pending {
diff --git a/core/tx_pool_test.go b/core/tx_pool_test.go
index e7f52075e..25993c258 100644
--- a/core/tx_pool_test.go
+++ b/core/tx_pool_test.go
@@ -118,21 +118,27 @@ func validateTxPoolInternals(pool *TxPool) error {
 
 // validateEvents checks that the correct number of transaction addition events
 // were fired on the pool's event feed.
-func validateEvents(events chan TxPreEvent, count int) error {
-	for i := 0; i < count; i++ {
+func validateEvents(events chan NewTxsEvent, count int) error {
+	var received []*types.Transaction
+
+	for len(received) < count {
 		select {
-		case <-events:
+		case ev := <-events:
+			received = append(received, ev.Txs...)
 		case <-time.After(time.Second):
-			return fmt.Errorf("event #%d not fired", i)
+			return fmt.Errorf("event #%d not fired", received)
 		}
 	}
+	if len(received) > count {
+		return fmt.Errorf("more than %d events fired: %v", count, received[count:])
+	}
 	select {
-	case tx := <-events:
-		return fmt.Errorf("more than %d events fired: %v", count, tx.Tx)
+	case ev := <-events:
+		return fmt.Errorf("more than %d events fired: %v", count, ev.Txs)
 
 	case <-time.After(50 * time.Millisecond):
 		// This branch should be "default", but it's a data race between goroutines,
-		// reading the event channel and pushng into it, so better wait a bit ensuring
+		// reading the event channel and pushing into it, so better wait a bit ensuring
 		// really nothing gets injected.
 	}
 	return nil
@@ -669,7 +675,7 @@ func TestTransactionGapFilling(t *testing.T) {
 	pool.currentState.AddBalance(account, big.NewInt(1000000))
 
 	// Keep track of transaction events to ensure all executables get announced
-	events := make(chan TxPreEvent, testTxPoolConfig.AccountQueue+5)
+	events := make(chan NewTxsEvent, testTxPoolConfig.AccountQueue+5)
 	sub := pool.txFeed.Subscribe(events)
 	defer sub.Unsubscribe()
 
@@ -920,7 +926,7 @@ func TestTransactionPendingLimiting(t *testing.T) {
 	pool.currentState.AddBalance(account, big.NewInt(1000000))
 
 	// Keep track of transaction events to ensure all executables get announced
-	events := make(chan TxPreEvent, testTxPoolConfig.AccountQueue+5)
+	events := make(chan NewTxsEvent, testTxPoolConfig.AccountQueue+5)
 	sub := pool.txFeed.Subscribe(events)
 	defer sub.Unsubscribe()
 
@@ -1140,7 +1146,7 @@ func TestTransactionPoolRepricing(t *testing.T) {
 	defer pool.Stop()
 
 	// Keep track of transaction events to ensure all executables get announced
-	events := make(chan TxPreEvent, 32)
+	events := make(chan NewTxsEvent, 32)
 	sub := pool.txFeed.Subscribe(events)
 	defer sub.Unsubscribe()
 
@@ -1327,7 +1333,7 @@ func TestTransactionPoolUnderpricing(t *testing.T) {
 	defer pool.Stop()
 
 	// Keep track of transaction events to ensure all executables get announced
-	events := make(chan TxPreEvent, 32)
+	events := make(chan NewTxsEvent, 32)
 	sub := pool.txFeed.Subscribe(events)
 	defer sub.Unsubscribe()
 
@@ -1433,7 +1439,7 @@ func TestTransactionPoolStableUnderpricing(t *testing.T) {
 	defer pool.Stop()
 
 	// Keep track of transaction events to ensure all executables get announced
-	events := make(chan TxPreEvent, 32)
+	events := make(chan NewTxsEvent, 32)
 	sub := pool.txFeed.Subscribe(events)
 	defer sub.Unsubscribe()
 
@@ -1495,7 +1501,7 @@ func TestTransactionReplacement(t *testing.T) {
 	defer pool.Stop()
 
 	// Keep track of transaction events to ensure all executables get announced
-	events := make(chan TxPreEvent, 32)
+	events := make(chan NewTxsEvent, 32)
 	sub := pool.txFeed.Subscribe(events)
 	defer sub.Unsubscribe()
 
diff --git a/eth/api_backend.go b/eth/api_backend.go
index 4ace9b594..91a7dc7e0 100644
--- a/eth/api_backend.go
+++ b/eth/api_backend.go
@@ -188,8 +188,8 @@ func (b *EthAPIBackend) TxPoolContent() (map[common.Address]types.Transactions,
 	return b.eth.TxPool().Content()
 }
 
-func (b *EthAPIBackend) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
-	return b.eth.TxPool().SubscribeTxPreEvent(ch)
+func (b *EthAPIBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
+	return b.eth.TxPool().SubscribeNewTxsEvent(ch)
 }
 
 func (b *EthAPIBackend) Downloader() *downloader.Downloader {
diff --git a/eth/filters/api.go b/eth/filters/api.go
index 1297b7478..592ad3b82 100644
--- a/eth/filters/api.go
+++ b/eth/filters/api.go
@@ -104,8 +104,8 @@ func (api *PublicFilterAPI) timeoutLoop() {
 // https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_newpendingtransactionfilter
 func (api *PublicFilterAPI) NewPendingTransactionFilter() rpc.ID {
 	var (
-		pendingTxs   = make(chan common.Hash)
-		pendingTxSub = api.events.SubscribePendingTxEvents(pendingTxs)
+		pendingTxs   = make(chan []common.Hash)
+		pendingTxSub = api.events.SubscribePendingTxs(pendingTxs)
 	)
 
 	api.filtersMu.Lock()
@@ -118,7 +118,7 @@ func (api *PublicFilterAPI) NewPendingTransactionFilter() rpc.ID {
 			case ph := <-pendingTxs:
 				api.filtersMu.Lock()
 				if f, found := api.filters[pendingTxSub.ID]; found {
-					f.hashes = append(f.hashes, ph)
+					f.hashes = append(f.hashes, ph...)
 				}
 				api.filtersMu.Unlock()
 			case <-pendingTxSub.Err():
@@ -144,13 +144,17 @@ func (api *PublicFilterAPI) NewPendingTransactions(ctx context.Context) (*rpc.Su
 	rpcSub := notifier.CreateSubscription()
 
 	go func() {
-		txHashes := make(chan common.Hash)
-		pendingTxSub := api.events.SubscribePendingTxEvents(txHashes)
+		txHashes := make(chan []common.Hash, 128)
+		pendingTxSub := api.events.SubscribePendingTxs(txHashes)
 
 		for {
 			select {
-			case h := <-txHashes:
-				notifier.Notify(rpcSub.ID, h)
+			case hashes := <-txHashes:
+				// To keep the original behaviour, send a single tx hash in one notification.
+				// TODO(rjl493456442) Send a batch of tx hashes in one notification
+				for _, h := range hashes {
+					notifier.Notify(rpcSub.ID, h)
+				}
 			case <-rpcSub.Err():
 				pendingTxSub.Unsubscribe()
 				return
diff --git a/eth/filters/filter.go b/eth/filters/filter.go
index 5dfe60e77..67b4612ae 100644
--- a/eth/filters/filter.go
+++ b/eth/filters/filter.go
@@ -36,7 +36,7 @@ type Backend interface {
 	GetReceipts(ctx context.Context, blockHash common.Hash) (types.Receipts, error)
 	GetLogs(ctx context.Context, blockHash common.Hash) ([][]*types.Log, error)
 
-	SubscribeTxPreEvent(chan<- core.TxPreEvent) event.Subscription
+	SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
 	SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription
 	SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription
 	SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription
diff --git a/eth/filters/filter_system.go b/eth/filters/filter_system.go
index bb11734a7..4e999cda8 100644
--- a/eth/filters/filter_system.go
+++ b/eth/filters/filter_system.go
@@ -59,7 +59,7 @@ const (
 
 const (
 
-	// txChanSize is the size of channel listening to TxPreEvent.
+	// txChanSize is the size of channel listening to NewTxsEvent.
 	// The number is referenced from the size of tx pool.
 	txChanSize = 4096
 	// rmLogsChanSize is the size of channel listening to RemovedLogsEvent.
@@ -80,7 +80,7 @@ type subscription struct {
 	created   time.Time
 	logsCrit  ethereum.FilterQuery
 	logs      chan []*types.Log
-	hashes    chan common.Hash
+	hashes    chan []common.Hash
 	headers   chan *types.Header
 	installed chan struct{} // closed when the filter is installed
 	err       chan error    // closed when the filter is uninstalled
@@ -95,7 +95,7 @@ type EventSystem struct {
 	lastHead  *types.Header
 
 	// Subscriptions
-	txSub         event.Subscription         // Subscription for new transaction event
+	txsSub        event.Subscription         // Subscription for new transaction event
 	logsSub       event.Subscription         // Subscription for new log event
 	rmLogsSub     event.Subscription         // Subscription for removed log event
 	chainSub      event.Subscription         // Subscription for new chain event
@@ -104,7 +104,7 @@ type EventSystem struct {
 	// Channels
 	install   chan *subscription         // install filter for event notification
 	uninstall chan *subscription         // remove filter for event notification
-	txCh      chan core.TxPreEvent       // Channel to receive new transaction event
+	txsCh     chan core.NewTxsEvent      // Channel to receive new transactions event
 	logsCh    chan []*types.Log          // Channel to receive new log event
 	rmLogsCh  chan core.RemovedLogsEvent // Channel to receive removed log event
 	chainCh   chan core.ChainEvent       // Channel to receive new chain event
@@ -123,14 +123,14 @@ func NewEventSystem(mux *event.TypeMux, backend Backend, lightMode bool) *EventS
 		lightMode: lightMode,
 		install:   make(chan *subscription),
 		uninstall: make(chan *subscription),
-		txCh:      make(chan core.TxPreEvent, txChanSize),
+		txsCh:     make(chan core.NewTxsEvent, txChanSize),
 		logsCh:    make(chan []*types.Log, logsChanSize),
 		rmLogsCh:  make(chan core.RemovedLogsEvent, rmLogsChanSize),
 		chainCh:   make(chan core.ChainEvent, chainEvChanSize),
 	}
 
 	// Subscribe events
-	m.txSub = m.backend.SubscribeTxPreEvent(m.txCh)
+	m.txsSub = m.backend.SubscribeNewTxsEvent(m.txsCh)
 	m.logsSub = m.backend.SubscribeLogsEvent(m.logsCh)
 	m.rmLogsSub = m.backend.SubscribeRemovedLogsEvent(m.rmLogsCh)
 	m.chainSub = m.backend.SubscribeChainEvent(m.chainCh)
@@ -138,7 +138,7 @@ func NewEventSystem(mux *event.TypeMux, backend Backend, lightMode bool) *EventS
 	m.pendingLogSub = m.mux.Subscribe(core.PendingLogsEvent{})
 
 	// Make sure none of the subscriptions are empty
-	if m.txSub == nil || m.logsSub == nil || m.rmLogsSub == nil || m.chainSub == nil ||
+	if m.txsSub == nil || m.logsSub == nil || m.rmLogsSub == nil || m.chainSub == nil ||
 		m.pendingLogSub.Closed() {
 		log.Crit("Subscribe for event system failed")
 	}
@@ -240,7 +240,7 @@ func (es *EventSystem) subscribeMinedPendingLogs(crit ethereum.FilterQuery, logs
 		logsCrit:  crit,
 		created:   time.Now(),
 		logs:      logs,
-		hashes:    make(chan common.Hash),
+		hashes:    make(chan []common.Hash),
 		headers:   make(chan *types.Header),
 		installed: make(chan struct{}),
 		err:       make(chan error),
@@ -257,7 +257,7 @@ func (es *EventSystem) subscribeLogs(crit ethereum.FilterQuery, logs chan []*typ
 		logsCrit:  crit,
 		created:   time.Now(),
 		logs:      logs,
-		hashes:    make(chan common.Hash),
+		hashes:    make(chan []common.Hash),
 		headers:   make(chan *types.Header),
 		installed: make(chan struct{}),
 		err:       make(chan error),
@@ -274,7 +274,7 @@ func (es *EventSystem) subscribePendingLogs(crit ethereum.FilterQuery, logs chan
 		logsCrit:  crit,
 		created:   time.Now(),
 		logs:      logs,
-		hashes:    make(chan common.Hash),
+		hashes:    make(chan []common.Hash),
 		headers:   make(chan *types.Header),
 		installed: make(chan struct{}),
 		err:       make(chan error),
@@ -290,7 +290,7 @@ func (es *EventSystem) SubscribeNewHeads(headers chan *types.Header) *Subscripti
 		typ:       BlocksSubscription,
 		created:   time.Now(),
 		logs:      make(chan []*types.Log),
-		hashes:    make(chan common.Hash),
+		hashes:    make(chan []common.Hash),
 		headers:   headers,
 		installed: make(chan struct{}),
 		err:       make(chan error),
@@ -298,9 +298,9 @@ func (es *EventSystem) SubscribeNewHeads(headers chan *types.Header) *Subscripti
 	return es.subscribe(sub)
 }
 
-// SubscribePendingTxEvents creates a subscription that writes transaction hashes for
+// SubscribePendingTxs creates a subscription that writes transaction hashes for
 // transactions that enter the transaction pool.
-func (es *EventSystem) SubscribePendingTxEvents(hashes chan common.Hash) *Subscription {
+func (es *EventSystem) SubscribePendingTxs(hashes chan []common.Hash) *Subscription {
 	sub := &subscription{
 		id:        rpc.NewID(),
 		typ:       PendingTransactionsSubscription,
@@ -348,9 +348,13 @@ func (es *EventSystem) broadcast(filters filterIndex, ev interface{}) {
 				}
 			}
 		}
-	case core.TxPreEvent:
+	case core.NewTxsEvent:
+		hashes := make([]common.Hash, 0, len(e.Txs))
+		for _, tx := range e.Txs {
+			hashes = append(hashes, tx.Hash())
+		}
 		for _, f := range filters[PendingTransactionsSubscription] {
-			f.hashes <- e.Tx.Hash()
+			f.hashes <- hashes
 		}
 	case core.ChainEvent:
 		for _, f := range filters[BlocksSubscription] {
@@ -446,7 +450,7 @@ func (es *EventSystem) eventLoop() {
 	// Ensure all subscriptions get cleaned up
 	defer func() {
 		es.pendingLogSub.Unsubscribe()
-		es.txSub.Unsubscribe()
+		es.txsSub.Unsubscribe()
 		es.logsSub.Unsubscribe()
 		es.rmLogsSub.Unsubscribe()
 		es.chainSub.Unsubscribe()
@@ -460,7 +464,7 @@ func (es *EventSystem) eventLoop() {
 	for {
 		select {
 		// Handle subscribed events
-		case ev := <-es.txCh:
+		case ev := <-es.txsCh:
 			es.broadcast(index, ev)
 		case ev := <-es.logsCh:
 			es.broadcast(index, ev)
@@ -495,7 +499,7 @@ func (es *EventSystem) eventLoop() {
 			close(f.err)
 
 		// System stopped
-		case <-es.txSub.Err():
+		case <-es.txsSub.Err():
 			return
 		case <-es.logsSub.Err():
 			return
diff --git a/eth/filters/filter_system_test.go b/eth/filters/filter_system_test.go
index b4df24b47..ff1af85a8 100644
--- a/eth/filters/filter_system_test.go
+++ b/eth/filters/filter_system_test.go
@@ -96,7 +96,7 @@ func (b *testBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*types
 	return logs, nil
 }
 
-func (b *testBackend) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
+func (b *testBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
 	return b.txFeed.Subscribe(ch)
 }
 
@@ -232,10 +232,7 @@ func TestPendingTxFilter(t *testing.T) {
 	fid0 := api.NewPendingTransactionFilter()
 
 	time.Sleep(1 * time.Second)
-	for _, tx := range transactions {
-		ev := core.TxPreEvent{Tx: tx}
-		txFeed.Send(ev)
-	}
+	txFeed.Send(core.NewTxsEvent{Txs: transactions})
 
 	timeout := time.Now().Add(1 * time.Second)
 	for {
diff --git a/eth/handler.go b/eth/handler.go
index c8f7e13f1..8993afe15 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -46,7 +46,7 @@ const (
 	softResponseLimit = 2 * 1024 * 1024 // Target maximum size of returned blocks, headers or node data.
 	estHeaderRlpSize  = 500             // Approximate size of an RLP encoded block header
 
-	// txChanSize is the size of channel listening to TxPreEvent.
+	// txChanSize is the size of channel listening to NewTxsEvent.
 	// The number is referenced from the size of tx pool.
 	txChanSize = 4096
 )
@@ -81,8 +81,8 @@ type ProtocolManager struct {
 	SubProtocols []p2p.Protocol
 
 	eventMux      *event.TypeMux
-	txCh          chan core.TxPreEvent
-	txSub         event.Subscription
+	txsCh         chan core.NewTxsEvent
+	txsSub        event.Subscription
 	minedBlockSub *event.TypeMuxSubscription
 
 	// channels for fetcher, syncer, txsyncLoop
@@ -204,8 +204,8 @@ func (pm *ProtocolManager) Start(maxPeers int) {
 	pm.maxPeers = maxPeers
 
 	// broadcast transactions
-	pm.txCh = make(chan core.TxPreEvent, txChanSize)
-	pm.txSub = pm.txpool.SubscribeTxPreEvent(pm.txCh)
+	pm.txsCh = make(chan core.NewTxsEvent, txChanSize)
+	pm.txsSub = pm.txpool.SubscribeNewTxsEvent(pm.txsCh)
 	go pm.txBroadcastLoop()
 
 	// broadcast mined blocks
@@ -220,7 +220,7 @@ func (pm *ProtocolManager) Start(maxPeers int) {
 func (pm *ProtocolManager) Stop() {
 	log.Info("Stopping Ethereum protocol")
 
-	pm.txSub.Unsubscribe()         // quits txBroadcastLoop
+	pm.txsSub.Unsubscribe()        // quits txBroadcastLoop
 	pm.minedBlockSub.Unsubscribe() // quits blockBroadcastLoop
 
 	// Quit the sync loop.
@@ -712,16 +712,23 @@ func (pm *ProtocolManager) BroadcastBlock(block *types.Block, propagate bool) {
 	}
 }
 
-// BroadcastTx will propagate a transaction to all peers which are not known to
+// BroadcastTxs will propagate a batch of transactions to all peers which are not known to
 // already have the given transaction.
-func (pm *ProtocolManager) BroadcastTx(hash common.Hash, tx *types.Transaction) {
-	// Broadcast transaction to a batch of peers not knowing about it
-	peers := pm.peers.PeersWithoutTx(hash)
-	//FIXME include this again: peers = peers[:int(math.Sqrt(float64(len(peers))))]
-	for _, peer := range peers {
-		peer.SendTransactions(types.Transactions{tx})
+func (pm *ProtocolManager) BroadcastTxs(txs types.Transactions) {
+	var txset = make(map[*peer]types.Transactions)
+
+	// Broadcast transactions to a batch of peers not knowing about it
+	for _, tx := range txs {
+		peers := pm.peers.PeersWithoutTx(tx.Hash())
+		for _, peer := range peers {
+			txset[peer] = append(txset[peer], tx)
+		}
+		log.Trace("Broadcast transaction", "hash", tx.Hash(), "recipients", len(peers))
+	}
+	// FIXME include this again: peers = peers[:int(math.Sqrt(float64(len(peers))))]
+	for peer, txs := range txset {
+		peer.SendTransactions(txs)
 	}
-	log.Trace("Broadcast transaction", "hash", hash, "recipients", len(peers))
 }
 
 // Mined broadcast loop
@@ -739,11 +746,11 @@ func (pm *ProtocolManager) minedBroadcastLoop() {
 func (pm *ProtocolManager) txBroadcastLoop() {
 	for {
 		select {
-		case event := <-pm.txCh:
-			pm.BroadcastTx(event.Tx.Hash(), event.Tx)
+		case event := <-pm.txsCh:
+			pm.BroadcastTxs(event.Txs)
 
 		// Err() channel will be closed when unsubscribing.
-		case <-pm.txSub.Err():
+		case <-pm.txsSub.Err():
 			return
 		}
 	}
diff --git a/eth/helper_test.go b/eth/helper_test.go
index 8a0260fc9..3d2ab0aba 100644
--- a/eth/helper_test.go
+++ b/eth/helper_test.go
@@ -124,7 +124,7 @@ func (p *testTxPool) Pending() (map[common.Address]types.Transactions, error) {
 	return batches, nil
 }
 
-func (p *testTxPool) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
+func (p *testTxPool) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
 	return p.txFeed.Subscribe(ch)
 }
 
diff --git a/eth/protocol.go b/eth/protocol.go
index 328d5b993..0e90e6a2e 100644
--- a/eth/protocol.go
+++ b/eth/protocol.go
@@ -103,9 +103,9 @@ type txPool interface {
 	// The slice should be modifiable by the caller.
 	Pending() (map[common.Address]types.Transactions, error)
 
-	// SubscribeTxPreEvent should return an event subscription of
-	// TxPreEvent and send events to the given channel.
-	SubscribeTxPreEvent(chan<- core.TxPreEvent) event.Subscription
+	// SubscribeNewTxsEvent should return an event subscription of
+	// NewTxsEvent and send events to the given channel.
+	SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
 }
 
 // statusData is the network packet for the status message.
diff --git a/eth/protocol_test.go b/eth/protocol_test.go
index b2f93d8dd..aa43dfa92 100644
--- a/eth/protocol_test.go
+++ b/eth/protocol_test.go
@@ -116,7 +116,7 @@ func testRecvTransactions(t *testing.T, protocol int) {
 			t.Errorf("added wrong tx hash: got %v, want %v", added[0].Hash(), tx.Hash())
 		}
 	case <-time.After(2 * time.Second):
-		t.Errorf("no TxPreEvent received within 2 seconds")
+		t.Errorf("no NewTxsEvent received within 2 seconds")
 	}
 }
 
diff --git a/ethstats/ethstats.go b/ethstats/ethstats.go
index a15d84615..c11601435 100644
--- a/ethstats/ethstats.go
+++ b/ethstats/ethstats.go
@@ -49,7 +49,7 @@ const (
 	// history request.
 	historyUpdateRange = 50
 
-	// txChanSize is the size of channel listening to TxPreEvent.
+	// txChanSize is the size of channel listening to NewTxsEvent.
 	// The number is referenced from the size of tx pool.
 	txChanSize = 4096
 	// chainHeadChanSize is the size of channel listening to ChainHeadEvent.
@@ -57,9 +57,9 @@ const (
 )
 
 type txPool interface {
-	// SubscribeTxPreEvent should return an event subscription of
-	// TxPreEvent and send events to the given channel.
-	SubscribeTxPreEvent(chan<- core.TxPreEvent) event.Subscription
+	// SubscribeNewTxsEvent should return an event subscription of
+	// NewTxsEvent and send events to the given channel.
+	SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
 }
 
 type blockChain interface {
@@ -150,8 +150,8 @@ func (s *Service) loop() {
 	headSub := blockchain.SubscribeChainHeadEvent(chainHeadCh)
 	defer headSub.Unsubscribe()
 
-	txEventCh := make(chan core.TxPreEvent, txChanSize)
-	txSub := txpool.SubscribeTxPreEvent(txEventCh)
+	txEventCh := make(chan core.NewTxsEvent, txChanSize)
+	txSub := txpool.SubscribeNewTxsEvent(txEventCh)
 	defer txSub.Unsubscribe()
 
 	// Start a goroutine that exhausts the subsciptions to avoid events piling up
diff --git a/internal/ethapi/backend.go b/internal/ethapi/backend.go
index af95d7906..c9ffe230c 100644
--- a/internal/ethapi/backend.go
+++ b/internal/ethapi/backend.go
@@ -65,7 +65,7 @@ type Backend interface {
 	GetPoolNonce(ctx context.Context, addr common.Address) (uint64, error)
 	Stats() (pending int, queued int)
 	TxPoolContent() (map[common.Address]types.Transactions, map[common.Address]types.Transactions)
-	SubscribeTxPreEvent(chan<- core.TxPreEvent) event.Subscription
+	SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
 
 	ChainConfig() *params.ChainConfig
 	CurrentBlock() *types.Block
diff --git a/les/api_backend.go b/les/api_backend.go
index 1d3c99513..dea33c470 100644
--- a/les/api_backend.go
+++ b/les/api_backend.go
@@ -136,8 +136,8 @@ func (b *LesApiBackend) TxPoolContent() (map[common.Address]types.Transactions,
 	return b.eth.txPool.Content()
 }
 
-func (b *LesApiBackend) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
-	return b.eth.txPool.SubscribeTxPreEvent(ch)
+func (b *LesApiBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
+	return b.eth.txPool.SubscribeNewTxsEvent(ch)
 }
 
 func (b *LesApiBackend) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription {
diff --git a/light/txpool.go b/light/txpool.go
index 94c8139cb..1fabc3dc5 100644
--- a/light/txpool.go
+++ b/light/txpool.go
@@ -321,9 +321,9 @@ func (pool *TxPool) Stop() {
 	log.Info("Transaction pool stopped")
 }
 
-// SubscribeTxPreEvent registers a subscription of core.TxPreEvent and
+// SubscribeNewTxsEvent registers a subscription of core.NewTxsEvent and
 // starts sending event to the given channel.
-func (pool *TxPool) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription {
+func (pool *TxPool) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
 	return pool.scope.Track(pool.txFeed.Subscribe(ch))
 }
 
@@ -412,7 +412,7 @@ func (self *TxPool) add(ctx context.Context, tx *types.Transaction) error {
 		// Notify the subscribers. This event is posted in a goroutine
 		// because it's possible that somewhere during the post "Remove transaction"
 		// gets called which will then wait for the global tx pool lock and deadlock.
-		go self.txFeed.Send(core.TxPreEvent{Tx: tx})
+		go self.txFeed.Send(core.NewTxsEvent{Txs: types.Transactions{tx}})
 	}
 
 	// Print a log message if low enough level is set
diff --git a/miner/worker.go b/miner/worker.go
index 48b0b2765..640e9032e 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -42,7 +42,7 @@ const (
 	resultQueueSize  = 10
 	miningLogAtDepth = 5
 
-	// txChanSize is the size of channel listening to TxPreEvent.
+	// txChanSize is the size of channel listening to NewTxsEvent.
 	// The number is referenced from the size of tx pool.
 	txChanSize = 4096
 	// chainHeadChanSize is the size of channel listening to ChainHeadEvent.
@@ -71,6 +71,7 @@ type Work struct {
 	family    *set.Set       // family set (used for checking uncle invalidity)
 	uncles    *set.Set       // uncle set
 	tcount    int            // tx count in cycle
+	gasPool   *core.GasPool  // available gas used to pack transactions
 
 	Block *types.Block // the new block
 
@@ -95,8 +96,8 @@ type worker struct {
 
 	// update loop
 	mux          *event.TypeMux
-	txCh         chan core.TxPreEvent
-	txSub        event.Subscription
+	txsCh        chan core.NewTxsEvent
+	txsSub       event.Subscription
 	chainHeadCh  chan core.ChainHeadEvent
 	chainHeadSub event.Subscription
 	chainSideCh  chan core.ChainSideEvent
@@ -137,7 +138,7 @@ func newWorker(config *params.ChainConfig, engine consensus.Engine, coinbase com
 		engine:         engine,
 		eth:            eth,
 		mux:            mux,
-		txCh:           make(chan core.TxPreEvent, txChanSize),
+		txsCh:          make(chan core.NewTxsEvent, txChanSize),
 		chainHeadCh:    make(chan core.ChainHeadEvent, chainHeadChanSize),
 		chainSideCh:    make(chan core.ChainSideEvent, chainSideChanSize),
 		chainDb:        eth.ChainDb(),
@@ -149,8 +150,8 @@ func newWorker(config *params.ChainConfig, engine consensus.Engine, coinbase com
 		agents:         make(map[Agent]struct{}),
 		unconfirmed:    newUnconfirmedBlocks(eth.BlockChain(), miningLogAtDepth),
 	}
-	// Subscribe TxPreEvent for tx pool
-	worker.txSub = eth.TxPool().SubscribeTxPreEvent(worker.txCh)
+	// Subscribe NewTxsEvent for tx pool
+	worker.txsSub = eth.TxPool().SubscribeNewTxsEvent(worker.txsCh)
 	// Subscribe events for blockchain
 	worker.chainHeadSub = eth.BlockChain().SubscribeChainHeadEvent(worker.chainHeadCh)
 	worker.chainSideSub = eth.BlockChain().SubscribeChainSideEvent(worker.chainSideCh)
@@ -241,7 +242,7 @@ func (self *worker) unregister(agent Agent) {
 }
 
 func (self *worker) update() {
-	defer self.txSub.Unsubscribe()
+	defer self.txsSub.Unsubscribe()
 	defer self.chainHeadSub.Unsubscribe()
 	defer self.chainSideSub.Unsubscribe()
 
@@ -258,15 +259,21 @@ func (self *worker) update() {
 			self.possibleUncles[ev.Block.Hash()] = ev.Block
 			self.uncleMu.Unlock()
 
-		// Handle TxPreEvent
-		case ev := <-self.txCh:
-			// Apply transaction to the pending state if we're not mining
+		// Handle NewTxsEvent
+		case ev := <-self.txsCh:
+			// Apply transactions to the pending state if we're not mining.
+			//
+			// Note all transactions received may not be continuous with transactions
+			// already included in the current mining block. These transactions will
+			// be automatically eliminated.
 			if atomic.LoadInt32(&self.mining) == 0 {
 				self.currentMu.Lock()
-				acc, _ := types.Sender(self.current.signer, ev.Tx)
-				txs := map[common.Address]types.Transactions{acc: {ev.Tx}}
+				txs := make(map[common.Address]types.Transactions)
+				for _, tx := range ev.Txs {
+					acc, _ := types.Sender(self.current.signer, tx)
+					txs[acc] = append(txs[acc], tx)
+				}
 				txset := types.NewTransactionsByPriceAndNonce(self.current.signer, txs)
-
 				self.current.commitTransactions(self.mux, txset, self.chain, self.coinbase)
 				self.updateSnapshot()
 				self.currentMu.Unlock()
@@ -278,7 +285,7 @@ func (self *worker) update() {
 			}
 
 		// System stopped
-		case <-self.txSub.Err():
+		case <-self.txsSub.Err():
 			return
 		case <-self.chainHeadSub.Err():
 			return
@@ -522,14 +529,16 @@ func (self *worker) updateSnapshot() {
 }
 
 func (env *Work) commitTransactions(mux *event.TypeMux, txs *types.TransactionsByPriceAndNonce, bc *core.BlockChain, coinbase common.Address) {
-	gp := new(core.GasPool).AddGas(env.header.GasLimit)
+	if env.gasPool == nil {
+		env.gasPool = new(core.GasPool).AddGas(env.header.GasLimit)
+	}
 
 	var coalescedLogs []*types.Log
 
 	for {
 		// If we don't have enough gas for any further transactions then we're done
-		if gp.Gas() < params.TxGas {
-			log.Trace("Not enough gas for further transactions", "gp", gp)
+		if env.gasPool.Gas() < params.TxGas {
+			log.Trace("Not enough gas for further transactions", "have", env.gasPool, "want", params.TxGas)
 			break
 		}
 		// Retrieve the next transaction and abort if all done
@@ -553,7 +562,7 @@ func (env *Work) commitTransactions(mux *event.TypeMux, txs *types.TransactionsB
 		// Start executing the transaction
 		env.state.Prepare(tx.Hash(), common.Hash{}, env.tcount)
 
-		err, logs := env.commitTransaction(tx, bc, coinbase, gp)
+		err, logs := env.commitTransaction(tx, bc, coinbase, env.gasPool)
 		switch err {
 		case core.ErrGasLimitReached:
 			// Pop the current out-of-gas transaction without shifting in the next from the account