From 56ed6152a11592d20220daf6322e94a009e6236d Mon Sep 17 00:00:00 2001 From: Felix Lange Date: Tue, 29 Mar 2016 03:08:16 +0200 Subject: core, eth, miner: improve shutdown synchronisation Shutting down geth prints hundreds of annoying error messages in some cases. The errors appear because the Stop method of eth.ProtocolManager, miner.Miner and core.TxPool is asynchronous. Left over peer sessions generate events which are processed after Stop even though the database has already been closed. The fix is to make Stop synchronous using sync.WaitGroup. For eth.ProtocolManager, in order to make use of WaitGroup safe, we need a way to stop new peer sessions from being added while waiting on the WaitGroup. The eth protocol Run function now selects on a signaling channel and adds to the WaitGroup only if ProtocolManager is not shutting down. For miner.worker and core.TxPool the number of goroutines is static, WaitGroup can be used in the usual way without additional synchronisation. --- core/tx_pool.go | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'core') diff --git a/core/tx_pool.go b/core/tx_pool.go index e997e8cd0..f2eb2bbdd 100644 --- a/core/tx_pool.go +++ b/core/tx_pool.go @@ -60,8 +60,7 @@ type stateFn func() (*state.StateDB, error) // two states over time as they are received and processed. type TxPool struct { config *ChainConfig - quit chan bool // Quitting channel - currentState stateFn // The state function which will allow us to do some pre checks + currentState stateFn // The state function which will allow us to do some pre checks pendingState *state.ManagedState gasLimit func() *big.Int // The current gas limit function callback minGasPrice *big.Int @@ -72,6 +71,8 @@ type TxPool struct { pending map[common.Hash]*types.Transaction // processable transactions queue map[common.Address]map[common.Hash]*types.Transaction + wg sync.WaitGroup // for shutdown sync + homestead bool } @@ -80,7 +81,6 @@ func NewTxPool(config *ChainConfig, eventMux *event.TypeMux, currentStateFn stat config: config, pending: make(map[common.Hash]*types.Transaction), queue: make(map[common.Address]map[common.Hash]*types.Transaction), - quit: make(chan bool), eventMux: eventMux, currentState: currentStateFn, gasLimit: gasLimitFn, @@ -90,12 +90,15 @@ func NewTxPool(config *ChainConfig, eventMux *event.TypeMux, currentStateFn stat events: eventMux.Subscribe(ChainHeadEvent{}, GasPriceChanged{}, RemovedTransactionEvent{}), } + pool.wg.Add(1) go pool.eventLoop() return pool } func (pool *TxPool) eventLoop() { + defer pool.wg.Done() + // Track chain events. When a chain events occurs (new chain canon block) // we need to know the new state. The new state will help us determine // the nonces in the managed state @@ -155,8 +158,8 @@ func (pool *TxPool) resetState() { } func (pool *TxPool) Stop() { - close(pool.quit) pool.events.Unsubscribe() + pool.wg.Wait() glog.V(logger.Info).Infoln("Transaction pool stopped") } -- cgit