Expose default gas price percentile configuration in CLI (#7497)

* Expose gas price percentile.

* Fix light eth_call.

* fix gas_price in light client

parity/cli/mod.rs

@@ -346,6 +346,7 @@ usage! {
 			ARG arg_password: (Vec<String>) = Vec::new(), or |c: &Config| otry!(c.account).password.clone(),
 			"--password=[FILE]...",
 			"Provide a file containing a password for unlocking an account. Leading and trailing whitespace is trimmed.",
+
 		["UI options"]
 			FLAG flag_force_ui: (bool) = false, or |c: &Config| otry!(c.ui).force.clone(),
 			"--force-ui",
@@ -696,6 +697,10 @@ usage! {
 			"--min-gas-price=[STRING]",
 			"Minimum amount of Wei per GAS to be paid for a transaction to be accepted for mining. Overrides --usd-per-tx.",
 
+			ARG arg_gas_price_percentile: (usize) = 50usize, or |c: &Config| otry!(c.mining).gas_price_percentile,
+			"--gas-price-percentile=[PCT]",
+			"Set PCT percentile gas price value from last 100 blocks as default gas price when sending transactions.",
+
 			ARG arg_author: (Option<String>) = None, or |c: &Config| otry!(c.mining).author.clone(),
 			"--author=[ADDRESS]",
 			"Specify the block author (aka \"coinbase\") address for sending block rewards from sealed blocks. NOTE: MINING WILL NOT WORK WITHOUT THIS OPTION.", // Sealing/Mining Option
@@ -1142,6 +1147,7 @@ struct Mining {
 	tx_time_limit: Option<u64>,
 	relay_set: Option<String>,
 	min_gas_price: Option<u64>,
+	gas_price_percentile: Option<usize>,
 	usd_per_tx: Option<String>,
 	usd_per_eth: Option<String>,
 	price_update_period: Option<String>,
@@ -1546,6 +1552,7 @@ mod tests {
 			arg_tx_time_limit: Some(100u64),
 			arg_relay_set: "cheap".into(),
 			arg_min_gas_price: Some(0u64),
+			arg_gas_price_percentile: 50usize,
 			arg_usd_per_tx: "0.0025".into(),
 			arg_usd_per_eth: "auto".into(),
 			arg_price_update_period: "hourly".into(),
@@ -1794,6 +1801,7 @@ mod tests {
 				work_queue_size: None,
 				relay_set: None,
 				min_gas_price: None,
+				gas_price_percentile: None,
 				usd_per_tx: None,
 				usd_per_eth: None,
 				price_update_period: Some("hourly".into()),

parity/configuration.rs

@@ -339,6 +339,7 @@ impl Configuration {
 				daemon: daemon,
 				logger_config: logger_config.clone(),
 				miner_options: self.miner_options()?,
+				gas_price_percentile: self.args.arg_gas_price_percentile,
 				ntp_servers: self.ntp_servers(),
 				ws_conf: ws_conf,
 				http_conf: http_conf,
@@ -1357,6 +1358,7 @@ mod tests {
 			daemon: None,
 			logger_config: Default::default(),
 			miner_options: Default::default(),
+			gas_price_percentile: 50,
 			ntp_servers: vec![
 				"0.parity.pool.ntp.org:123".into(),
 				"1.parity.pool.ntp.org:123".into(),

parity/rpc_apis.rs

@@ -226,6 +226,7 @@ pub struct FullDependencies {
 	pub fetch: FetchClient,
 	pub remote: parity_reactor::Remote,
 	pub whisper_rpc: Option<::whisper::RpcFactory>,
+	pub gas_price_percentile: usize,
 }
 
 impl FullDependencies {
@@ -241,7 +242,7 @@ impl FullDependencies {
 			($namespace:ident, $handler:expr, $deps:expr, $nonces:expr) => {
 				{
 					let deps = &$deps;
-					let dispatcher = FullDispatcher::new(deps.client.clone(), deps.miner.clone(), $nonces);
+					let dispatcher = FullDispatcher::new(deps.client.clone(), deps.miner.clone(), $nonces, deps.gas_price_percentile);
 					if deps.signer_service.is_enabled() {
 						$handler.extend_with($namespace::to_delegate(SigningQueueClient::new(&deps.signer_service, dispatcher, deps.remote.clone(), &deps.secret_store)))
 					} else {
@@ -256,6 +257,7 @@ impl FullDependencies {
 			self.client.clone(),
 			self.miner.clone(),
 			nonces.clone(),
+			self.gas_price_percentile,
 		);
 		for api in apis {
 			match *api {
@@ -277,6 +279,7 @@ impl FullDependencies {
 							pending_nonce_from_queue: self.geth_compatibility,
 							allow_pending_receipt_query: !self.geth_compatibility,
 							send_block_number_in_get_work: !self.geth_compatibility,
+							gas_price_percentile: self.gas_price_percentile,
 						}
 					);
 					handler.extend_with(client.to_delegate());
@@ -422,6 +425,7 @@ pub struct LightDependencies<T> {
 	pub geth_compatibility: bool,
 	pub remote: parity_reactor::Remote,
 	pub whisper_rpc: Option<::whisper::RpcFactory>,
+	pub gas_price_percentile: usize,
 }
 
 impl<C: LightChainClient + 'static> LightDependencies<C> {
@@ -440,6 +444,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 			self.cache.clone(),
 			self.transaction_queue.clone(),
 			Arc::new(Mutex::new(dispatch::Reservations::with_pool(self.fetch.pool()))),
+			self.gas_price_percentile,
 		);
 
 		macro_rules! add_signing_methods {
@@ -477,6 +482,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 						self.transaction_queue.clone(),
 						self.secret_store.clone(),
 						self.cache.clone(),
+						self.gas_price_percentile,
 					);
 					handler.extend_with(Eth::to_delegate(client.clone()));
 
@@ -492,6 +498,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 						self.sync.clone(),
 						self.cache.clone(),
 						self.remote.clone(),
+						self.gas_price_percentile,
 					);
 					self.client.add_listener(
 						Arc::downgrade(&client.handler()) as Weak<::light::client::LightChainNotify>
@@ -521,6 +528,7 @@ impl<C: LightChainClient + 'static> LightDependencies<C> {
 						signer,
 						self.dapps_address.clone(),
 						self.ws_address.clone(),
+						self.gas_price_percentile,
 					).to_delegate());
 
 					if !for_generic_pubsub {

parity/run.rs

@@ -87,6 +87,7 @@ pub struct RunCmd {
 	pub daemon: Option<String>,
 	pub logger_config: LogConfig,
 	pub miner_options: MinerOptions,
+	pub gas_price_percentile: usize,
 	pub ntp_servers: Vec<String>,
 	pub ws_conf: rpc::WsConfiguration,
 	pub http_conf: rpc::HttpConfiguration,
@@ -358,6 +359,7 @@ fn execute_light(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) ->
 		geth_compatibility: cmd.geth_compatibility,
 		remote: event_loop.remote(),
 		whisper_rpc: whisper_factory,
+		gas_price_percentile: cmd.gas_price_percentile,
 	});
 
 	let dependencies = rpc::Dependencies {
@@ -761,6 +763,7 @@ pub fn execute(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) -> R
 		fetch: fetch.clone(),
 		remote: event_loop.remote(),
 		whisper_rpc: whisper_factory,
+		gas_price_percentile: cmd.gas_price_percentile,
 	});
 
 	let dependencies = rpc::Dependencies {

rpc/src/v1/helpers/dispatch.rs

@@ -88,6 +88,7 @@ pub struct FullDispatcher<C, M> {
 	client: Arc<C>,
 	miner: Arc<M>,
 	nonces: Arc<Mutex<nonce::Reservations>>,
+	gas_price_percentile: usize,
 }
 
 impl<C, M> FullDispatcher<C, M> {
@@ -96,11 +97,13 @@ impl<C, M> FullDispatcher<C, M> {
 		client: Arc<C>,
 		miner: Arc<M>,
 		nonces: Arc<Mutex<nonce::Reservations>>,
+		gas_price_percentile: usize,
 	) -> Self {
 		FullDispatcher {
 			client,
 			miner,
 			nonces,
+			gas_price_percentile,
 		}
 	}
 }
@@ -111,6 +114,7 @@ impl<C, M> Clone for FullDispatcher<C, M> {
 			client: self.client.clone(),
 			miner: self.miner.clone(),
 			nonces: self.nonces.clone(),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 }
@@ -148,7 +152,9 @@ impl<C: MiningBlockChainClient, M: MinerService> Dispatcher for FullDispatcher<C
 			used_default_from: request.from.is_none(),
 			to: request.to,
 			nonce,
-			gas_price: request.gas_price.unwrap_or_else(|| default_gas_price(&*self.client, &*self.miner)),
+			gas_price: request.gas_price.unwrap_or_else(|| {
+				default_gas_price(&*self.client, &*self.miner, self.gas_price_percentile)
+			}),
 			gas: request.gas.unwrap_or_else(|| self.miner.sensible_gas_limit()),
 			value: request.value.unwrap_or_else(|| 0.into()),
 			data: request.data.unwrap_or_else(Vec::new),
@@ -218,8 +224,8 @@ pub fn fetch_gas_price_corpus(
 				})
 			})
 			.map(move |prices| {
-				// produce a corpus from the vector, cache it, and return
-				// the median as the intended gas price.
+				// produce a corpus from the vector and cache it.
+				// It's later used to get a percentile for default gas price.
 				let corpus: ::stats::Corpus<_> = prices.into();
 				cache.lock().set_gas_price_corpus(corpus.clone());
 				corpus
@@ -258,6 +264,8 @@ pub struct LightDispatcher {
 	pub transaction_queue: Arc<RwLock<LightTransactionQueue>>,
 	/// Nonce reservations
 	pub nonces: Arc<Mutex<nonce::Reservations>>,
+	/// Gas Price percentile value used as default gas price.
+	pub gas_price_percentile: usize,
 }
 
 impl LightDispatcher {
@@ -271,6 +279,7 @@ impl LightDispatcher {
 		cache: Arc<Mutex<LightDataCache>>,
 		transaction_queue: Arc<RwLock<LightTransactionQueue>>,
 		nonces: Arc<Mutex<nonce::Reservations>>,
+		gas_price_percentile: usize,
 	) -> Self {
 		LightDispatcher {
 			sync,
@@ -279,6 +288,7 @@ impl LightDispatcher {
 			cache,
 			transaction_queue,
 			nonces,
+			gas_price_percentile,
 		}
 	}
 
@@ -345,15 +355,16 @@ impl Dispatcher for LightDispatcher {
 		};
 
 		// fast path for known gas price.
+		let gas_price_percentile = self.gas_price_percentile;
 		let gas_price = match request_gas_price {
 			Some(gas_price) => Either::A(future::ok(with_gas_price(gas_price))),
 			None => Either::B(fetch_gas_price_corpus(
 				self.sync.clone(),
 				self.client.clone(),
 				self.on_demand.clone(),
 				self.cache.clone()
-			).and_then(|corp| match corp.median() {
-				Some(median) => Ok(*median),
+			).and_then(move |corp| match corp.percentile(gas_price_percentile) {
+				Some(percentile) => Ok(*percentile),
 				None => Ok(DEFAULT_GAS_PRICE), // fall back to default on error.
 			}).map(with_gas_price))
 		};
@@ -738,11 +749,11 @@ fn decrypt(accounts: &AccountProvider, address: Address, msg: Bytes, password: S
 }
 
 /// Extract the default gas price from a client and miner.
-pub fn default_gas_price<C, M>(client: &C, miner: &M) -> U256 where
+pub fn default_gas_price<C, M>(client: &C, miner: &M, percentile: usize) -> U256 where
 	C: MiningBlockChainClient,
 	M: MinerService,
 {
-	client.gas_price_corpus(100).median().cloned().unwrap_or_else(|| miner.sensible_gas_price())
+	client.gas_price_corpus(100).percentile(percentile).cloned().unwrap_or_else(|| miner.sensible_gas_price())
 }
 
 /// Convert RPC confirmation payload to signer confirmation payload.

rpc/src/v1/helpers/light_fetch.rs

@@ -60,6 +60,8 @@ pub struct LightFetch {
 	pub sync: Arc<LightSync>,
 	/// The light data cache.
 	pub cache: Arc<Mutex<Cache>>,
+	/// Gas Price percentile
+	pub gas_price_percentile: usize,
 }
 
 /// Extract a transaction at given index.
@@ -203,15 +205,16 @@ impl LightFetch {
 			None => Either::B(self.account(from, id).map(|acc| acc.map(|a| a.nonce))),
 		};
 
+		let gas_price_percentile = self.gas_price_percentile;
 		let gas_price_fut = match req.gas_price {
 			Some(price) => Either::A(future::ok(price)),
 			None => Either::B(dispatch::fetch_gas_price_corpus(
 				self.sync.clone(),
 				self.client.clone(),
 				self.on_demand.clone(),
 				self.cache.clone(),
-			).map(|corp| match corp.median() {
-				Some(median) => *median,
+			).map(move |corp| match corp.percentile(gas_price_percentile) {
+				Some(percentile) => *percentile,
 				None => DEFAULT_GAS_PRICE.into(),
 			}))
 		};

rpc/src/v1/impls/eth.rs

@@ -66,6 +66,8 @@ pub struct EthClientOptions {
 	pub allow_pending_receipt_query: bool,
 	/// Send additional block number when asking for work
 	pub send_block_number_in_get_work: bool,
+	/// Gas Price Percentile used as default gas price.
+	pub gas_price_percentile: usize,
 }
 
 impl EthClientOptions {
@@ -84,6 +86,7 @@ impl Default for EthClientOptions {
 			pending_nonce_from_queue: false,
 			allow_pending_receipt_query: true,
 			send_block_number_in_get_work: true,
+			gas_price_percentile: 50,
 		}
 	}
 }
@@ -338,7 +341,7 @@ impl<C, SN: ?Sized, S: ?Sized, M, EM> Eth for EthClient<C, SN, S, M, EM> where
 	}
 
 	fn gas_price(&self) -> Result<RpcU256> {
-		Ok(RpcU256::from(default_gas_price(&*self.client, &*self.miner)))
+		Ok(RpcU256::from(default_gas_price(&*self.client, &*self.miner, self.options.gas_price_percentile)))
 	}
 
 	fn accounts(&self, meta: Metadata) -> Result<Vec<RpcH160>> {

rpc/src/v1/impls/eth_pubsub.rs

@@ -92,12 +92,14 @@ impl EthPubSubClient<LightFetch> {
 		sync: Arc<LightSync>,
 		cache: Arc<Mutex<Cache>>,
 		remote: Remote,
+		gas_price_percentile: usize,
 	) -> Self {
 		let fetch = LightFetch {
 			client,
 			on_demand,
 			sync,
-			cache
+			cache,
+			gas_price_percentile,
 		};
 		EthPubSubClient::new(Arc::new(fetch), remote)
 	}

rpc/src/v1/impls/light/eth.rs

@@ -62,6 +62,7 @@ pub struct EthClient<T> {
 	accounts: Arc<AccountProvider>,
 	cache: Arc<Mutex<LightDataCache>>,
 	polls: Mutex<PollManager<PollFilter>>,
+	gas_price_percentile: usize,
 }
 
 impl<T> Clone for EthClient<T> {
@@ -75,6 +76,7 @@ impl<T> Clone for EthClient<T> {
 			accounts: self.accounts.clone(),
 			cache: self.cache.clone(),
 			polls: Mutex::new(PollManager::new()),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 }
@@ -89,15 +91,17 @@ impl<T: LightChainClient + 'static> EthClient<T> {
 		transaction_queue: Arc<RwLock<TransactionQueue>>,
 		accounts: Arc<AccountProvider>,
 		cache: Arc<Mutex<LightDataCache>>,
+		gas_price_percentile: usize,
 	) -> Self {
 		EthClient {
-			sync: sync,
-			client: client,
-			on_demand: on_demand,
-			transaction_queue: transaction_queue,
-			accounts: accounts,
-			cache: cache,
+			sync,
+			client,
+			on_demand,
+			transaction_queue,
+			accounts,
+			cache,
 			polls: Mutex::new(PollManager::new()),
+			gas_price_percentile,
 		}
 	}
 
@@ -108,6 +112,7 @@ impl<T: LightChainClient + 'static> EthClient<T> {
 			on_demand: self.on_demand.clone(),
 			sync: self.sync.clone(),
 			cache: self.cache.clone(),
+			gas_price_percentile: self.gas_price_percentile,
 		}
 	}
 
@@ -239,7 +244,7 @@ impl<T: LightChainClient + 'static> Eth for EthClient<T> {
 
 	fn gas_price(&self) -> Result<RpcU256> {
 		Ok(self.cache.lock().gas_price_corpus()
-			.and_then(|c| c.median().cloned())
+			.and_then(|c| c.percentile(self.gas_price_percentile).cloned())
 			.map(RpcU256::from)
 			.unwrap_or_else(Default::default))
 	}