trie: store nodes as pointers

This avoids memory copies when unwrapping node interface values.

name      old time/op  new time/op  delta
Get        388ns ± 8%   215ns ± 2%  -44.56%  (p=0.000 n=15+15)
GetDB      363ns ± 3%   202ns ± 2%  -44.21%  (p=0.000 n=15+15)
UpdateBE  1.57µs ± 2%  1.29µs ± 3%  -17.80%  (p=0.000 n=13+15)
UpdateLE  1.92µs ± 2%  1.61µs ± 2%  -16.25%  (p=0.000 n=14+14)
HashBE    2.16µs ± 6%  2.18µs ± 6%     ~     (p=0.436 n=15+15)
HashLE    7.43µs ± 3%  7.21µs ± 3%   -2.96%  (p=0.000 n=15+13)
This commit is contained in:
Felix Lange 2016-10-14 03:17:06 +02:00
parent f63c6c008f
commit bfe3da83e2
6 changed files with 90 additions and 99 deletions

View file

@ -62,16 +62,18 @@ func (h *hasher) hash(n node, db DatabaseWriter, force bool) (node, node, error)
if err != nil {
return hashNode{}, n, err
}
// Cache the hash and RLP blob of the ndoe for later reuse
// Cache the hash of the ndoe for later reuse.
if hash, ok := hashed.(hashNode); ok && !force {
switch cached := cached.(type) {
case shortNode:
case *shortNode:
cached = cached.copy()
cached.hash = hash
if db != nil {
cached.dirty = false
}
return hashed, cached, nil
case fullNode:
case *fullNode:
cached = cached.copy()
cached.hash = hash
if db != nil {
cached.dirty = false
@ -89,40 +91,43 @@ func (h *hasher) hashChildren(original node, db DatabaseWriter) (node, node, err
var err error
switch n := original.(type) {
case shortNode:
case *shortNode:
// Hash the short node's child, caching the newly hashed subtree
cached := n
cached.Key = common.CopyBytes(cached.Key)
collapsed, cached := n.copy(), n.copy()
collapsed.Key = compactEncode(n.Key)
cached.Key = common.CopyBytes(n.Key)
n.Key = compactEncode(n.Key)
if _, ok := n.Val.(valueNode); !ok {
if n.Val, cached.Val, err = h.hash(n.Val, db, false); err != nil {
return n, original, err
collapsed.Val, cached.Val, err = h.hash(n.Val, db, false)
if err != nil {
return original, original, err
}
}
if n.Val == nil {
n.Val = valueNode(nil) // Ensure that nil children are encoded as empty strings.
if collapsed.Val == nil {
collapsed.Val = valueNode(nil) // Ensure that nil children are encoded as empty strings.
}
return n, cached, nil
return collapsed, cached, nil
case fullNode:
case *fullNode:
// Hash the full node's children, caching the newly hashed subtrees
cached := fullNode{dirty: n.dirty}
collapsed := n.copy()
cached := &fullNode{dirty: n.dirty}
for i := 0; i < 16; i++ {
if n.Children[i] != nil {
if n.Children[i], cached.Children[i], err = h.hash(n.Children[i], db, false); err != nil {
return n, original, err
collapsed.Children[i], cached.Children[i], err = h.hash(n.Children[i], db, false)
if err != nil {
return original, original, err
}
} else {
n.Children[i] = valueNode(nil) // Ensure that nil children are encoded as empty strings.
collapsed.Children[i] = valueNode(nil) // Ensure that nil children are encoded as empty strings.
}
}
cached.Children[16] = n.Children[16]
if n.Children[16] == nil {
n.Children[16] = valueNode(nil)
if collapsed.Children[16] == nil {
collapsed.Children[16] = valueNode(nil)
}
return n, cached, nil
return collapsed, cached, nil
default:
// Value and hash nodes don't have children so they're left as were
@ -140,6 +145,7 @@ func (h *hasher) store(n node, db DatabaseWriter, force bool) (node, error) {
if err := rlp.Encode(h.tmp, n); err != nil {
panic("encode error: " + err.Error())
}
if h.tmp.Len() < 32 && !force {
return n, nil // Nodes smaller than 32 bytes are stored inside their parent
}

View file

@ -56,11 +56,11 @@ func (it *Iterator) makeKey() []byte {
key := it.keyBuf[:0]
for _, se := range it.nodeIt.stack {
switch node := se.node.(type) {
case fullNode:
case *fullNode:
if se.child <= 16 {
key = append(key, byte(se.child))
}
case shortNode:
case *shortNode:
if hasTerm(node.Key) {
key = append(key, node.Key[:len(node.Key)-1]...)
} else {
@ -148,7 +148,7 @@ func (it *NodeIterator) step() error {
if (ancestor == common.Hash{}) {
ancestor = parent.parent
}
if node, ok := parent.node.(fullNode); ok {
if node, ok := parent.node.(*fullNode); ok {
// Full node, traverse all children, then the node itself
if parent.child >= len(node.Children) {
break
@ -164,7 +164,7 @@ func (it *NodeIterator) step() error {
break
}
}
} else if node, ok := parent.node.(shortNode); ok {
} else if node, ok := parent.node.(*shortNode); ok {
// Short node, traverse the pointer singleton child, then the node itself
if parent.child >= 0 {
break

View file

@ -49,23 +49,26 @@ type (
)
// EncodeRLP encodes a full node into the consensus RLP format.
func (n fullNode) EncodeRLP(w io.Writer) error {
func (n *fullNode) EncodeRLP(w io.Writer) error {
return rlp.Encode(w, n.Children)
}
func (n *fullNode) copy() *fullNode { copy := *n; return &copy }
func (n *shortNode) copy() *shortNode { copy := *n; return &copy }
// Cache accessors to retrieve precalculated values (avoid lengthy type switches).
func (n fullNode) cache() (hashNode, bool) { return n.hash, n.dirty }
func (n shortNode) cache() (hashNode, bool) { return n.hash, n.dirty }
func (n *fullNode) cache() (hashNode, bool) { return n.hash, n.dirty }
func (n *shortNode) cache() (hashNode, bool) { return n.hash, n.dirty }
func (n hashNode) cache() (hashNode, bool) { return nil, true }
func (n valueNode) cache() (hashNode, bool) { return nil, true }
// Pretty printing.
func (n fullNode) String() string { return n.fstring("") }
func (n shortNode) String() string { return n.fstring("") }
func (n *fullNode) String() string { return n.fstring("") }
func (n *shortNode) String() string { return n.fstring("") }
func (n hashNode) String() string { return n.fstring("") }
func (n valueNode) String() string { return n.fstring("") }
func (n fullNode) fstring(ind string) string {
func (n *fullNode) fstring(ind string) string {
resp := fmt.Sprintf("[\n%s ", ind)
for i, node := range n.Children {
if node == nil {
@ -76,7 +79,7 @@ func (n fullNode) fstring(ind string) string {
}
return resp + fmt.Sprintf("\n%s] ", ind)
}
func (n shortNode) fstring(ind string) string {
func (n *shortNode) fstring(ind string) string {
return fmt.Sprintf("{%x: %v} ", n.Key, n.Val.fstring(ind+" "))
}
func (n hashNode) fstring(ind string) string {
@ -127,17 +130,17 @@ func decodeShort(hash, buf, elems []byte) (node, error) {
if err != nil {
return nil, fmt.Errorf("invalid value node: %v", err)
}
return shortNode{key, valueNode(val), hash, false}, nil
return &shortNode{key, valueNode(val), hash, false}, nil
}
r, _, err := decodeRef(rest)
if err != nil {
return nil, wrapError(err, "val")
}
return shortNode{key, r, hash, false}, nil
return &shortNode{key, r, hash, false}, nil
}
func decodeFull(hash, buf, elems []byte) (fullNode, error) {
n := fullNode{hash: hash}
func decodeFull(hash, buf, elems []byte) (*fullNode, error) {
n := &fullNode{hash: hash}
for i := 0; i < 16; i++ {
cld, rest, err := decodeRef(elems)
if err != nil {

View file

@ -44,7 +44,7 @@ func (t *Trie) Prove(key []byte) []rlp.RawValue {
tn := t.root
for len(key) > 0 && tn != nil {
switch n := tn.(type) {
case shortNode:
case *shortNode:
if len(key) < len(n.Key) || !bytes.Equal(n.Key, key[:len(n.Key)]) {
// The trie doesn't contain the key.
tn = nil
@ -53,7 +53,7 @@ func (t *Trie) Prove(key []byte) []rlp.RawValue {
key = key[len(n.Key):]
}
nodes = append(nodes, n)
case fullNode:
case *fullNode:
tn = n.Children[key[0]]
key = key[1:]
nodes = append(nodes, n)
@ -130,13 +130,13 @@ func VerifyProof(rootHash common.Hash, key []byte, proof []rlp.RawValue) (value
func get(tn node, key []byte) ([]byte, node) {
for len(key) > 0 {
switch n := tn.(type) {
case shortNode:
case *shortNode:
if len(key) < len(n.Key) || !bytes.Equal(n.Key, key[:len(n.Key)]) {
return nil, nil
}
tn = n.Val
key = key[len(n.Key):]
case fullNode:
case *fullNode:
tn = n.Children[key[0]]
key = key[1:]
case hashNode:

View file

@ -212,12 +212,12 @@ func (s *TrieSync) children(req *request) ([]*request, error) {
children := []child{}
switch node := (*req.object).(type) {
case shortNode:
case *shortNode:
children = []child{{
node: &node.Val,
depth: req.depth + len(node.Key),
}}
case fullNode:
case *fullNode:
for i := 0; i < 17; i++ {
if node.Children[i] != nil {
children = append(children, child{

View file

@ -120,27 +120,25 @@ func (t *Trie) tryGet(origNode node, key []byte, pos int) (value []byte, newnode
return nil, nil, false, nil
case valueNode:
return n, n, false, nil
case shortNode:
case *shortNode:
if len(key)-pos < len(n.Key) || !bytes.Equal(n.Key, key[pos:pos+len(n.Key)]) {
// key not found in trie
return nil, n, false, nil
}
value, newnode, didResolve, err = t.tryGet(n.Val, key, pos+len(n.Key))
if err == nil && didResolve {
n = n.copy()
n.Val = newnode
return value, n, didResolve, err
} else {
return value, origNode, didResolve, err
}
case fullNode:
child := n.Children[key[pos]]
value, newnode, didResolve, err = t.tryGet(child, key, pos+1)
return value, n, didResolve, err
case *fullNode:
value, newnode, didResolve, err = t.tryGet(n.Children[key[pos]], key, pos+1)
if err == nil && didResolve {
n = n.copy()
n.Children[key[pos]] = newnode
return value, n, didResolve, err
} else {
return value, origNode, didResolve, err
}
return value, n, didResolve, err
case hashNode:
child, err := t.resolveHash(n, key[:pos], key[pos:])
if err != nil {
@ -199,22 +197,19 @@ func (t *Trie) insert(n node, prefix, key []byte, value node) (bool, node, error
return true, value, nil
}
switch n := n.(type) {
case shortNode:
case *shortNode:
matchlen := prefixLen(key, n.Key)
// If the whole key matches, keep this short node as is
// and only update the value.
if matchlen == len(n.Key) {
dirty, nn, err := t.insert(n.Val, append(prefix, key[:matchlen]...), key[matchlen:], value)
if err != nil {
return false, nil, err
if !dirty || err != nil {
return false, n, err
}
if !dirty {
return false, n, nil
}
return true, shortNode{n.Key, nn, nil, true}, nil
return true, &shortNode{n.Key, nn, nil, true}, nil
}
// Otherwise branch out at the index where they differ.
branch := fullNode{dirty: true}
branch := &fullNode{dirty: true}
var err error
_, branch.Children[n.Key[matchlen]], err = t.insert(nil, append(prefix, n.Key[:matchlen+1]...), n.Key[matchlen+1:], n.Val)
if err != nil {
@ -229,21 +224,19 @@ func (t *Trie) insert(n node, prefix, key []byte, value node) (bool, node, error
return true, branch, nil
}
// Otherwise, replace it with a short node leading up to the branch.
return true, shortNode{key[:matchlen], branch, nil, true}, nil
return true, &shortNode{key[:matchlen], branch, nil, true}, nil
case fullNode:
case *fullNode:
dirty, nn, err := t.insert(n.Children[key[0]], append(prefix, key[0]), key[1:], value)
if err != nil {
return false, nil, err
}
if !dirty {
return false, n, nil
if !dirty || err != nil {
return false, n, err
}
n = n.copy()
n.Children[key[0]], n.hash, n.dirty = nn, nil, true
return true, n, nil
case nil:
return true, shortNode{key, value, nil, true}, nil
return true, &shortNode{key, value, nil, true}, nil
case hashNode:
// We've hit a part of the trie that isn't loaded yet. Load
@ -254,11 +247,8 @@ func (t *Trie) insert(n node, prefix, key []byte, value node) (bool, node, error
return false, nil, err
}
dirty, nn, err := t.insert(rn, prefix, key, value)
if err != nil {
return false, nil, err
}
if !dirty {
return false, rn, nil
if !dirty || err != nil {
return false, rn, err
}
return true, nn, nil
@ -291,7 +281,7 @@ func (t *Trie) TryDelete(key []byte) error {
// nodes on the way up after deleting recursively.
func (t *Trie) delete(n node, prefix, key []byte) (bool, node, error) {
switch n := n.(type) {
case shortNode:
case *shortNode:
matchlen := prefixLen(key, n.Key)
if matchlen < len(n.Key) {
return false, n, nil // don't replace n on mismatch
@ -304,33 +294,28 @@ func (t *Trie) delete(n node, prefix, key []byte) (bool, node, error) {
// subtrie must contain at least two other values with keys
// longer than n.Key.
dirty, child, err := t.delete(n.Val, append(prefix, key[:len(n.Key)]...), key[len(n.Key):])
if err != nil {
return false, nil, err
}
if !dirty {
return false, n, nil
if !dirty || err != nil {
return false, n, err
}
switch child := child.(type) {
case shortNode:
case *shortNode:
// Deleting from the subtrie reduced it to another
// short node. Merge the nodes to avoid creating a
// shortNode{..., shortNode{...}}. Use concat (which
// always creates a new slice) instead of append to
// avoid modifying n.Key since it might be shared with
// other nodes.
return true, shortNode{concat(n.Key, child.Key...), child.Val, nil, true}, nil
return true, &shortNode{concat(n.Key, child.Key...), child.Val, nil, true}, nil
default:
return true, shortNode{n.Key, child, nil, true}, nil
return true, &shortNode{n.Key, child, nil, true}, nil
}
case fullNode:
case *fullNode:
dirty, nn, err := t.delete(n.Children[key[0]], append(prefix, key[0]), key[1:])
if err != nil {
return false, nil, err
}
if !dirty {
return false, n, nil
if !dirty || err != nil {
return false, n, err
}
n = n.copy()
n.Children[key[0]], n.hash, n.dirty = nn, nil, true
// Check how many non-nil entries are left after deleting and
@ -365,14 +350,14 @@ func (t *Trie) delete(n node, prefix, key []byte) (bool, node, error) {
if err != nil {
return false, nil, err
}
if cnode, ok := cnode.(shortNode); ok {
if cnode, ok := cnode.(*shortNode); ok {
k := append([]byte{byte(pos)}, cnode.Key...)
return true, shortNode{k, cnode.Val, nil, true}, nil
return true, &shortNode{k, cnode.Val, nil, true}, nil
}
}
// Otherwise, n is replaced by a one-nibble short node
// containing the child.
return true, shortNode{[]byte{byte(pos)}, n.Children[pos], nil, true}, nil
return true, &shortNode{[]byte{byte(pos)}, n.Children[pos], nil, true}, nil
}
// n still contains at least two values and cannot be reduced.
return true, n, nil
@ -392,11 +377,8 @@ func (t *Trie) delete(n node, prefix, key []byte) (bool, node, error) {
return false, nil, err
}
dirty, nn, err := t.delete(rn, prefix, key)
if err != nil {
return false, nil, err
}
if !dirty {
return false, rn, nil
if !dirty || err != nil {
return false, rn, err
}
return true, nn, nil