Merge pull request #6389 from paritytech/trie

Trie optimizations

util/src/journaldb/archivedb.rs

@@ -17,6 +17,7 @@
 //! Disk-backed `HashDB` implementation.
 
 use std::collections::HashMap;
+use std::collections::hash_map::Entry;
 use std::sync::Arc;
 use rlp::*;
 use hashdb::*;
@@ -66,23 +67,28 @@ impl ArchiveDB {
 
 impl HashDB for ArchiveDB {
 	fn keys(&self) -> HashMap<H256, i32> {
-		let mut ret: HashMap<H256, i32> = HashMap::new();
+		let mut ret: HashMap<H256, i32> = self.backing.iter(self.column)
-		for (key, _) in self.backing.iter(self.column) {
+			.map(|(key, _)| (H256::from_slice(&*key), 1))
-			let h = H256::from_slice(&*key);
+			.collect();
-			ret.insert(h, 1);
-		}
 
 		for (key, refs) in self.overlay.keys() {
-			let refs = *ret.get(&key).unwrap_or(&0) + refs;
+			match ret.entry(key) {
-			ret.insert(key, refs);
+				Entry::Occupied(mut entry) => {
+					*entry.get_mut() += refs;
+				},
+				Entry::Vacant(entry) => {
+					entry.insert(refs);
+				}
+			}
 		}
 		ret
 	}
 
 	fn get(&self, key: &H256) -> Option<DBValue> {
-		let k = self.overlay.raw(key);
+		if let Some((d, rc)) = self.overlay.raw(key) {
-		if let Some((d, rc)) = k {
+			if rc > 0 {
-			if rc > 0 { return Some(d); }
+				return Some(d);
+			}
 		}
 		self.payload(key)
 	}

util/src/journaldb/earlymergedb.rs

@@ -18,6 +18,7 @@
 
 use std::fmt;
 use std::collections::HashMap;
+use std::collections::hash_map::Entry;
 use std::sync::Arc;
 use parking_lot::RwLock;
 use heapsize::HeapSizeOf;
@@ -311,23 +312,28 @@ impl EarlyMergeDB {
 
 impl HashDB for EarlyMergeDB {
 	fn keys(&self) -> HashMap<H256, i32> {
-		let mut ret: HashMap<H256, i32> = HashMap::new();
+		let mut ret: HashMap<H256, i32> = self.backing.iter(self.column)
-		for (key, _) in self.backing.iter(self.column) {
+			.map(|(key, _)| (H256::from_slice(&*key), 1))
-			let h = H256::from_slice(&*key);
+			.collect();
-			ret.insert(h, 1);
-		}
 
 		for (key, refs) in self.overlay.keys() {
-			let refs = *ret.get(&key).unwrap_or(&0) + refs;
+			match ret.entry(key) {
-			ret.insert(key, refs);
+				Entry::Occupied(mut entry) => {
+					*entry.get_mut() += refs;
+				},
+				Entry::Vacant(entry) => {
+					entry.insert(refs);
+				}
+			}
 		}
 		ret
 	}
 
 	fn get(&self, key: &H256) -> Option<DBValue> {
-		let k = self.overlay.raw(key);
+		if let Some((d, rc)) = self.overlay.raw(key) {
-		if let Some((d, rc)) = k {
+			if rc > 0 {
-			if rc > 0 { return Some(d) }
+				return Some(d)
+			}
 		}
 		self.payload(key)
 	}

util/src/journaldb/overlayrecentdb.rs

@@ -17,6 +17,7 @@
 //! `JournalDB` over in-memory overlay
 
 use std::collections::HashMap;
+use std::collections::hash_map::Entry;
 use std::sync::Arc;
 use parking_lot::RwLock;
 use heapsize::HeapSizeOf;
@@ -407,23 +408,28 @@ impl JournalDB for OverlayRecentDB {
 
 impl HashDB for OverlayRecentDB {
 	fn keys(&self) -> HashMap<H256, i32> {
-		let mut ret: HashMap<H256, i32> = HashMap::new();
+		let mut ret: HashMap<H256, i32> = self.backing.iter(self.column)
-		for (key, _) in self.backing.iter(self.column) {
+			.map(|(key, _)| (H256::from_slice(&*key), 1))
-			let h = H256::from_slice(&*key);
+			.collect();
-			ret.insert(h, 1);
-		}
 
 		for (key, refs) in self.transaction_overlay.keys() {
-			let refs = *ret.get(&key).unwrap_or(&0) + refs;
+			match ret.entry(key) {
-			ret.insert(key, refs);
+				Entry::Occupied(mut entry) => {
+					*entry.get_mut() += refs;
+				},
+				Entry::Vacant(entry) => {
+					entry.insert(refs);
+				}
+			}
 		}
 		ret
 	}
 
 	fn get(&self, key: &H256) -> Option<DBValue> {
-		let k = self.transaction_overlay.raw(key);
+		if let Some((d, rc)) = self.transaction_overlay.raw(key) {
-		if let Some((d, rc)) = k {
+			if rc > 0 {
-			if rc > 0 { return Some(d) }
+				return Some(d)
+			}
 		}
 		let v = {
 			let journal_overlay = self.journal_overlay.read();

util/src/journaldb/refcounteddb.rs

@@ -198,7 +198,7 @@ impl JournalDB for RefCountedDB {
 	fn consolidate(&mut self, mut with: MemoryDB) {
 		for (key, (value, rc)) in with.drain() {
 			for _ in 0..rc {
-				self.emplace(key.clone(), value.clone());
+				self.emplace(key, value.clone());
 			}
 
 			for _ in rc..0 {

util/src/memorydb.rs

@@ -16,14 +16,14 @@
 
 //! Reference-counted memory-based `HashDB` implementation.
 
-use hash::*;
-use rlp::*;
-use sha3::*;
-use hashdb::*;
-use heapsize::*;
 use std::mem;
 use std::collections::HashMap;
 use std::collections::hash_map::Entry;
+use heapsize::HeapSizeOf;
+use hash::{H256FastMap, H256};
+use rlp::NULL_RLP;
+use sha3::*;
+use hashdb::*;
 
 /// Reference-counted memory-based `HashDB` implementation.
 ///
@@ -181,7 +181,13 @@ impl HashDB for MemoryDB {
 	}
 
 	fn keys(&self) -> HashMap<H256, i32> {
-		self.data.iter().filter_map(|(k, v)| if v.1 != 0 {Some((k.clone(), v.1))} else {None}).collect()
+		self.data.iter()
+			.filter_map(|(k, v)| if v.1 != 0 {
+				Some((*k, v.1))
+			} else {
+				None
+			})
+			.collect()
 	}
 
 	fn contains(&self, key: &H256) -> bool {
@@ -200,16 +206,17 @@ impl HashDB for MemoryDB {
 			return SHA3_NULL_RLP.clone();
 		}
 		let key = value.sha3();
-		if match self.data.get_mut(&key) {
+		match self.data.entry(key) {
-			Some(&mut (ref mut old_value, ref mut rc @ -0x80000000i32 ... 0)) => {
+			Entry::Occupied(mut entry) => {
+				let &mut (ref mut old_value, ref mut rc) = entry.get_mut();
+				if *rc >= -0x80000000i32 && *rc <= 0 {
 					*old_value = DBValue::from_slice(value);
+				}
 				*rc += 1;
-				false
 			},
-			Some(&mut (_, ref mut x)) => { *x += 1; false } ,
+			Entry::Vacant(entry) => {
-			None => true,
+				entry.insert((DBValue::from_slice(value), 1));
-		}{	// ... None falls through into...
+			},
-			self.data.insert(key.clone(), (DBValue::from_slice(value), 1));
 		}
 		key
 	}
@@ -219,17 +226,18 @@ impl HashDB for MemoryDB {
 			return;
 		}
 
-		match self.data.get_mut(&key) {
+		match self.data.entry(key) {
-			Some(&mut (ref mut old_value, ref mut rc @ -0x80000000i32 ... 0)) => {
+			Entry::Occupied(mut entry) => {
+				let &mut (ref mut old_value, ref mut rc) = entry.get_mut();
+				if *rc >= -0x80000000i32 && *rc <= 0 {
 					*old_value = value;
-				*rc += 1;
-				return;
-			},
-			Some(&mut (_, ref mut x)) => { *x += 1; return; } ,
-			None => {},
 				}
-		// ... None falls through into...
+				*rc += 1;
-		self.data.insert(key, (value, 1));
+			},
+			Entry::Vacant(entry) => {
+				entry.insert((value, 1));
+			},
+		}
 	}
 
 	fn remove(&mut self, key: &H256) {
@@ -237,11 +245,14 @@ impl HashDB for MemoryDB {
 			return;
 		}
 
-		if match self.data.get_mut(key) {
+		match self.data.entry(*key) {
-			Some(&mut (_, ref mut x)) => { *x -= 1; false }
+			Entry::Occupied(mut entry) => {
-			None => true
+				let &mut (_, ref mut rc) = entry.get_mut();
-		}{	// ... None falls through into...
+				*rc -= 1;
-			self.data.insert(key.clone(), (DBValue::new(), -1));
+			},
+			Entry::Vacant(entry) => {
+				entry.insert((DBValue::new(), -1));
+			},
 		}
 	}
 }

util/src/overlaydb.rs

@@ -16,13 +16,14 @@
 
 //! Disk-backed `HashDB` implementation.
 
+use std::sync::Arc;
+use std::collections::HashMap;
+use std::collections::hash_map::Entry;
 use error::*;
 use hash::*;
 use rlp::*;
 use hashdb::*;
 use memorydb::*;
-use std::sync::*;
-use std::collections::HashMap;
 use kvdb::{KeyValueDB, DBTransaction};
 
 /// Implementation of the `HashDB` trait for a disk-backed database with a memory overlay.
@@ -125,19 +126,27 @@ impl OverlayDB {
 
 impl HashDB for OverlayDB {
 	fn keys(&self) -> HashMap<H256, i32> {
-		let mut ret: HashMap<H256, i32> = HashMap::new();
+		let mut ret: HashMap<H256, i32> = self.backing.iter(self.column)
-		for (key, _) in self.backing.iter(self.column) {
+			.map(|(key, _)| {
 				let h = H256::from_slice(&*key);
 				let r = self.payload(&h).unwrap().1;
-			ret.insert(h, r as i32);
+				(h, r as i32)
-		}
+			})
+			.collect();
 
 		for (key, refs) in self.overlay.keys() {
-			let refs = *ret.get(&key).unwrap_or(&0) + refs;
+			match ret.entry(key) {
-			ret.insert(key, refs);
+				Entry::Occupied(mut entry) => {
+					*entry.get_mut() += refs;
+				},
+				Entry::Vacant(entry) => {
+					entry.insert(refs);
+				}
+			}
 		}
 		ret
 	}
+
 	fn get(&self, key: &H256) -> Option<DBValue> {
 		// return ok if positive; if negative, check backing - might be enough references there to make
 		// it positive again.
@@ -165,6 +174,7 @@ impl HashDB for OverlayDB {
 			_ => None,
 		}
 	}
+
 	fn contains(&self, key: &H256) -> bool {
 		// return ok if positive; if negative, check backing - might be enough references there to make
 		// it positive again.
@@ -185,6 +195,7 @@ impl HashDB for OverlayDB {
 			}
 		}
 	}
+
 	fn insert(&mut self, value: &[u8]) -> H256 { self.overlay.insert(value) }
 	fn emplace(&mut self, key: H256, value: DBValue) { self.overlay.emplace(key, value); }
 	fn remove(&mut self, key: &H256) { self.overlay.remove(key); }

util/src/trie/triedb.rs

@@ -217,10 +217,12 @@ impl<'a> TrieDBIterator<'a> {
 		Ok(r)
 	}
 
-	fn seek_descend<'key>(&mut self, node_data: DBValue, key: &NibbleSlice<'key>) -> super::Result<()> {
+	fn seek<'key>(&mut self, mut node_data: DBValue, mut key: NibbleSlice<'key>) -> super::Result<()> {
+		loop {
+			let (data, mid) = {
 				let node = Node::decoded(&node_data);
 				match node {
-			Node::Leaf(ref slice, _) => {
+					Node::Leaf(slice, _) => {
 						if slice == key {
 							self.trail.push(Crumb {
 								status: Status::At,
@@ -234,7 +236,7 @@ impl<'a> TrieDBIterator<'a> {
 						}
 
 						self.key_nibbles.extend(slice.iter());
-				Ok(())
+						return Ok(())
 					},
 					Node::Extension(ref slice, ref item) => {
 						if key.starts_with(slice) {
@@ -244,10 +246,10 @@ impl<'a> TrieDBIterator<'a> {
 							});
 							self.key_nibbles.extend(slice.iter());
 							let data = self.db.get_raw_or_lookup(&*item)?;
-					self.seek_descend(data, &key.mid(slice.len()))
+							(data, slice.len())
 						} else {
 							self.descend(&node_data)?;
-					Ok(())
+							return Ok(())
 						}
 					},
 					Node::Branch(ref nodes, _) => match key.is_empty() {
@@ -256,7 +258,7 @@ impl<'a> TrieDBIterator<'a> {
 								status: Status::At,
 								node: node.clone().into(),
 							});
-					Ok(())
+							return Ok(())
 						},
 						false => {
 							let i = key.at(0);
@@ -266,10 +268,15 @@ impl<'a> TrieDBIterator<'a> {
 							});
 							self.key_nibbles.push(i);
 							let child = self.db.get_raw_or_lookup(&*nodes[i as usize])?;
-					self.seek_descend(child, &key.mid(1))
+							(child, 1)
 						}
 					},
-			_ => Ok(())
+					_ => return Ok(()),
+				}
+			};
+
+			node_data = data;
+			key = key.mid(mid);
 		}
 	}
 
@@ -314,7 +321,7 @@ impl<'a> TrieIterator for TrieDBIterator<'a> {
 		self.trail.clear();
 		self.key_nibbles.clear();
 		let root_rlp = self.db.root_data()?;
-		self.seek_descend(root_rlp, &NibbleSlice::new(key))
+		self.seek(root_rlp, NibbleSlice::new(key))
 	}
 }