[#2210] pilorama: Reduce the amount of keys per node

Under high load we are limited by the _amount_ of keys we need to update
in a single transaction. In this commit we try storing all state
with a single key.

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
This commit is contained in:
Evgenii Stratonikov 2023-01-17 16:16:50 +03:00 committed by fyrchik
parent 64a5294b27
commit 165a600624
4 changed files with 126 additions and 122 deletions

View file

@ -156,8 +156,7 @@ func (t *boltForest) TreeMove(d CIDDescriptor, treeID string, m *Move) (*LogMove
return nil, ErrReadOnlyMode
}
var lm LogMove
lm.Move = *m
lm := *m
return &lm, t.db.Batch(func(tx *bbolt.Tx) error {
bLog, bTree, err := t.getTreeBuckets(tx, d.CID, treeID)
if err != nil {
@ -227,7 +226,7 @@ func (t *boltForest) TreeAddByPath(d CIDDescriptor, treeID string, attr string,
ts := t.getLatestTimestamp(bLog, d.Position, d.Size)
lm = make([]LogMove, len(path)-i+1)
for j := i; j < len(path); j++ {
lm[j-i].Move = Move{
lm[j-i] = Move{
Parent: node,
Meta: Meta{
Time: ts,
@ -245,7 +244,7 @@ func (t *boltForest) TreeAddByPath(d CIDDescriptor, treeID string, attr string,
node = lm[j-i].Child
}
lm[len(lm)-1].Move = Move{
lm[len(lm)-1] = Move{
Parent: node,
Meta: Meta{
Time: ts,
@ -274,17 +273,14 @@ func (t *boltForest) getLatestTimestamp(bLog *bbolt.Bucket, pos, size int) uint6
// findSpareID returns random unused ID.
func (t *boltForest) findSpareID(bTree *bbolt.Bucket) uint64 {
id := uint64(rand.Int63())
var key [9]byte
key[0] = 't'
binary.LittleEndian.PutUint64(key[1:], id)
key := make([]byte, 9)
for {
if bTree.Get(key[:]) == nil {
_, _, _, ok := t.getState(bTree, stateKey(key, id))
if !ok {
return id
}
id = uint64(rand.Int63())
binary.LittleEndian.PutUint64(key[1:], id)
}
}
@ -420,8 +416,12 @@ func (t *boltForest) applyOperation(logBucket, treeBucket *bbolt.Bucket, ms []*M
// 1. Undo up until the desired timestamp is here.
for len(key) == 8 && ms[0].Time < binary.BigEndian.Uint64(key) {
b.Reset(value)
if err := t.logFromBytes(&tmp, r); err != nil {
return err
tmp.Child = r.ReadU64LE()
tmp.Parent = r.ReadU64LE()
tmp.Time = r.ReadVarUint()
if r.Err != nil {
return r.Err
}
if err := t.undo(&tmp, treeBucket, cKey[:]); err != nil {
return err
@ -433,7 +433,7 @@ func (t *boltForest) applyOperation(logBucket, treeBucket *bbolt.Bucket, ms []*M
// Loop invariant: key represents the next stored timestamp after ms[i].Time.
// 2. Insert the operation.
lm.Move = *ms[i]
*lm = *ms[i]
if err := t.do(logBucket, treeBucket, cKey[:], lm); err != nil {
return err
}
@ -445,11 +445,10 @@ func (t *boltForest) applyOperation(logBucket, treeBucket *bbolt.Bucket, ms []*M
// 3. Re-apply all other operations.
for len(key) == 8 && (i == len(ms)-1 || binary.BigEndian.Uint64(key) < ms[i+1].Time) {
b.Reset(value)
if err := t.logFromBytes(&tmp, r); err != nil {
if err := t.logFromBytes(&tmp, value); err != nil {
return err
}
if err := t.do(logBucket, treeBucket, cKey[:], &tmp); err != nil {
if err := t.redo(treeBucket, cKey[:], &tmp, value[16:]); err != nil {
return err
}
key, value = c.Next()
@ -460,39 +459,42 @@ func (t *boltForest) applyOperation(logBucket, treeBucket *bbolt.Bucket, ms []*M
}
func (t *boltForest) do(lb *bbolt.Bucket, b *bbolt.Bucket, key []byte, op *LogMove) error {
currParent := b.Get(parentKey(key, op.Child))
op.HasOld = currParent != nil
if currParent != nil { // node is already in tree
op.Old.Parent = binary.LittleEndian.Uint64(currParent)
if err := op.Old.Meta.FromBytes(b.Get(metaKey(key, op.Child))); err != nil {
return err
}
} else {
op.HasOld = false
op.Old = nodeInfo{}
}
binary.BigEndian.PutUint64(key, op.Time)
if err := lb.Put(key[:8], t.logToBytes(op)); err != nil {
rawLog := t.logToBytes(op)
if err := lb.Put(key[:8], rawLog); err != nil {
return err
}
if op.Child == op.Parent || t.isAncestor(b, op.Child, op.Parent) {
return nil
return t.redo(b, key, op, rawLog[16:])
}
if currParent == nil {
if err := b.Put(timestampKey(key, op.Child), toUint64(op.Time)); err != nil {
return err
}
func (t *boltForest) redo(b *bbolt.Bucket, key []byte, op *LogMove, rawMeta []byte) error {
var err error
parent, ts, currMeta, inTree := t.getState(b, stateKey(key, op.Child))
if inTree {
err = t.putState(b, oldKey(key, op.Time), parent, ts, currMeta)
} else {
parent := binary.LittleEndian.Uint64(currParent)
ts = op.Time
err = b.Delete(oldKey(key, op.Time))
}
if err != nil || op.Child == op.Parent || t.isAncestor(b, op.Child, op.Parent) {
return err
}
if inTree {
if err := b.Delete(childrenKey(key, op.Child, parent)); err != nil {
return err
}
for i := range op.Old.Meta.Items {
if isAttributeInternal(op.Old.Meta.Items[i].Key) {
key = internalKey(key, op.Old.Meta.Items[i].Key, string(op.Old.Meta.Items[i].Value), parent, op.Child)
var meta Meta
if err := meta.FromBytes(currMeta); err != nil {
return err
}
for i := range meta.Items {
if isAttributeInternal(meta.Items[i].Key) {
key = internalKey(key, meta.Items[i].Key, string(meta.Items[i].Value), parent, op.Child)
err := b.Delete(key)
if err != nil {
return err
@ -500,17 +502,16 @@ func (t *boltForest) do(lb *bbolt.Bucket, b *bbolt.Bucket, key []byte, op *LogMo
}
}
}
return t.addNode(b, key, op.Child, op.Parent, op.Meta)
return t.addNode(b, key, op.Child, op.Parent, ts, op.Meta, rawMeta)
}
// removeNode removes node keys from the tree except the children key or its parent.
func (t *boltForest) removeNode(b *bbolt.Bucket, key []byte, node, parent Node) error {
if err := b.Delete(parentKey(key, node)); err != nil {
return err
}
k := stateKey(key, node)
_, _, rawMeta, _ := t.getState(b, k)
var meta Meta
var k = metaKey(key, node)
if err := meta.FromBytes(b.Get(k)); err == nil {
if err := meta.FromBytes(rawMeta); err == nil {
for i := range meta.Items {
if isAttributeInternal(meta.Items[i].Key) {
err := b.Delete(internalKey(nil, meta.Items[i].Key, string(meta.Items[i].Value), parent, node))
@ -520,23 +521,16 @@ func (t *boltForest) removeNode(b *bbolt.Bucket, key []byte, node, parent Node)
}
}
}
if err := b.Delete(metaKey(key, node)); err != nil {
return err
}
return b.Delete(timestampKey(key, node))
return b.Delete(k)
}
// addNode adds node keys to the tree except the timestamp key.
func (t *boltForest) addNode(b *bbolt.Bucket, key []byte, child, parent Node, meta Meta) error {
err := b.Put(parentKey(key, child), toUint64(parent))
if err != nil {
func (t *boltForest) addNode(b *bbolt.Bucket, key []byte, child, parent Node, time Timestamp, meta Meta, rawMeta []byte) error {
if err := t.putState(b, stateKey(key, child), parent, time, rawMeta); err != nil {
return err
}
err = b.Put(childrenKey(key, child, parent), []byte{1})
if err != nil {
return err
}
err = b.Put(metaKey(key, child), meta.Bytes())
err := b.Put(childrenKey(key, child, parent), []byte{1})
if err != nil {
return err
}
@ -564,22 +558,28 @@ func (t *boltForest) undo(m *LogMove, b *bbolt.Bucket, key []byte) error {
return err
}
if !m.HasOld {
parent, ts, rawMeta, ok := t.getState(b, oldKey(key, m.Time))
if !ok {
return t.removeNode(b, key, m.Child, m.Parent)
}
return t.addNode(b, key, m.Child, m.Old.Parent, m.Old.Meta)
var meta Meta
if err := meta.FromBytes(rawMeta); err != nil {
return err
}
return t.addNode(b, key, m.Child, parent, ts, meta, rawMeta)
}
func (t *boltForest) isAncestor(b *bbolt.Bucket, parent, child Node) bool {
key := make([]byte, 9)
key[0] = 'p'
key[0] = 's'
for node := child; node != parent; {
binary.LittleEndian.PutUint64(key[1:], node)
rawParent := b.Get(key)
if len(rawParent) != 8 {
parent, _, _, ok := t.getState(b, key)
if !ok {
return false
}
node = binary.LittleEndian.Uint64(rawParent)
node = parent
}
return true
}
@ -619,10 +619,7 @@ func (t *boltForest) TreeGetByPath(cid cidSDK.ID, treeID string, attr string, pa
return nil
}
var (
childID [9]byte
maxTimestamp uint64
)
var maxTimestamp uint64
c := b.Cursor()
@ -632,7 +629,7 @@ func (t *boltForest) TreeGetByPath(cid cidSDK.ID, treeID string, attr string, pa
for len(childKey) == len(attrKey)+8 && bytes.Equal(attrKey, childKey[:len(childKey)-8]) {
child := binary.LittleEndian.Uint64(childKey[len(childKey)-8:])
if latest {
ts := binary.LittleEndian.Uint64(b.Get(timestampKey(childID[:], child)))
_, ts, _, _ := t.getState(b, stateKey(make([]byte, 9), child))
if ts >= maxTimestamp {
nodes = append(nodes[:0], child)
maxTimestamp = ts
@ -655,7 +652,7 @@ func (t *boltForest) TreeGetMeta(cid cidSDK.ID, treeID string, nodeID Node) (Met
return Meta{}, 0, ErrDegradedMode
}
key := parentKey(make([]byte, 9), nodeID)
key := stateKey(make([]byte, 9), nodeID)
var m Meta
var parentID uint64
@ -667,10 +664,11 @@ func (t *boltForest) TreeGetMeta(cid cidSDK.ID, treeID string, nodeID Node) (Met
}
b := treeRoot.Bucket(dataBucket)
if data := b.Get(key); len(data) == 8 {
if data := b.Get(key); len(data) != 0 {
parentID = binary.LittleEndian.Uint64(data)
}
return m.FromBytes(b.Get(metaKey(key, nodeID)))
_, _, meta, _ := t.getState(b, stateKey(key, nodeID))
return m.FromBytes(meta)
})
return m, parentID, err
@ -828,41 +826,31 @@ loop:
}
func (t *boltForest) moveFromBytes(m *Move, data []byte) error {
r := io.NewBinReaderFromBuf(data)
m.Child = r.ReadU64LE()
m.Parent = r.ReadU64LE()
m.Meta.DecodeBinary(r)
return r.Err
return t.logFromBytes(m, data)
}
func (t *boltForest) logFromBytes(lm *LogMove, r *io.BinReader) error {
lm.Child = r.ReadU64LE()
lm.Parent = r.ReadU64LE()
lm.Meta.DecodeBinary(r)
lm.HasOld = r.ReadBool()
if lm.HasOld {
lm.Old.Parent = r.ReadU64LE()
lm.Old.Meta.DecodeBinary(r)
}
return r.Err
func (t *boltForest) logFromBytes(lm *LogMove, data []byte) error {
lm.Child = binary.LittleEndian.Uint64(data)
lm.Parent = binary.LittleEndian.Uint64(data[8:])
return lm.Meta.FromBytes(data[16:])
}
func (t *boltForest) logToBytes(lm *LogMove) []byte {
w := io.NewBufBinWriter()
size := 8 + 8 + lm.Meta.Size() + 1
if lm.HasOld {
size += 8 + lm.Old.Meta.Size()
}
//if lm.HasOld {
// size += 8 + lm.Old.Meta.Size()
//}
w.Grow(size)
w.WriteU64LE(lm.Child)
w.WriteU64LE(lm.Parent)
lm.Meta.EncodeBinary(w.BinWriter)
w.WriteBool(lm.HasOld)
if lm.HasOld {
w.WriteU64LE(lm.Old.Parent)
lm.Old.Meta.EncodeBinary(w.BinWriter)
}
//w.WriteBool(lm.HasOld)
//if lm.HasOld {
// w.WriteU64LE(lm.Old.Parent)
// lm.Old.Meta.EncodeBinary(w.BinWriter)
//}
return w.Bytes()
}
@ -870,25 +858,37 @@ func bucketName(cid cidSDK.ID, treeID string) []byte {
return []byte(cid.String() + treeID)
}
// 't' + node (id) -> timestamp when the node first appeared.
func timestampKey(key []byte, child Node) []byte {
key[0] = 't'
// 'o' + time -> old meta.
func oldKey(key []byte, ts Timestamp) []byte {
key[0] = 'o'
binary.LittleEndian.PutUint64(key[1:], ts)
return key[:9]
}
// 's' + child ID -> parent + timestamp of the first appearance + meta.
func stateKey(key []byte, child Node) []byte {
key[0] = 's'
binary.LittleEndian.PutUint64(key[1:], child)
return key[:9]
}
// 'p' + node (id) -> parent (id).
func parentKey(key []byte, child Node) []byte {
key[0] = 'p'
binary.LittleEndian.PutUint64(key[1:], child)
return key[:9]
func (t *boltForest) putState(b *bbolt.Bucket, key []byte, parent Node, timestamp Timestamp, meta []byte) error {
data := make([]byte, len(meta)+8+8)
binary.LittleEndian.PutUint64(data, parent)
binary.LittleEndian.PutUint64(data[8:], timestamp)
copy(data[16:], meta)
return b.Put(key, data)
}
// 'm' + node (id) -> serialized meta.
func metaKey(key []byte, child Node) []byte {
key[0] = 'm'
binary.LittleEndian.PutUint64(key[1:], child)
return key[:9]
func (t *boltForest) getState(b *bbolt.Bucket, key []byte) (Node, Timestamp, []byte, bool) {
data := b.Get(key)
if data == nil {
return 0, 0, nil, false
}
parent := binary.LittleEndian.Uint64(data)
timestamp := binary.LittleEndian.Uint64(data[8:])
return parent, timestamp, data[16:], true
}
// 'c' + parent (id) + child (id) -> 0/1.

View file

@ -44,7 +44,7 @@ func (f *memoryForest) TreeMove(d CIDDescriptor, treeID string, op *Move) (*LogM
lm := s.do(op)
s.operations = append(s.operations, lm)
return &lm, nil
return &lm.Move, nil
}
// TreeAddByPath implements the Forest interface.
@ -66,20 +66,21 @@ func (f *memoryForest) TreeAddByPath(d CIDDescriptor, treeID string, attr string
i, node := s.getPathPrefix(attr, path)
lm := make([]LogMove, len(path)-i+1)
for j := i; j < len(path); j++ {
lm[j-i] = s.do(&Move{
op := s.do(&Move{
Parent: node,
Meta: Meta{
Time: s.timestamp(d.Position, d.Size),
Items: []KeyValue{{Key: attr, Value: []byte(path[j])}}},
Child: s.findSpareID(),
})
node = lm[j-i].Child
s.operations = append(s.operations, lm[j-i])
lm[j-i] = op.Move
node = op.Child
s.operations = append(s.operations, op)
}
mCopy := make([]KeyValue, len(m))
copy(mCopy, m)
lm[len(lm)-1] = s.do(&Move{
op := s.do(&Move{
Parent: node,
Meta: Meta{
Time: s.timestamp(d.Position, d.Size),
@ -87,6 +88,7 @@ func (f *memoryForest) TreeAddByPath(d CIDDescriptor, treeID string, attr string
},
Child: s.findSpareID(),
})
lm[len(lm)-1] = op.Move
return lm, nil
}

View file

@ -6,9 +6,15 @@ type nodeInfo struct {
Meta Meta
}
type move struct {
Move
HasOld bool
Old nodeInfo
}
// state represents state being replicated.
type state struct {
operations []LogMove
operations []move
tree
}
@ -20,7 +26,7 @@ func newState() *state {
}
// undo un-does op and changes s in-place.
func (s *state) undo(op *LogMove) {
func (s *state) undo(op *move) {
children := s.tree.childMap[op.Parent]
for i := range children {
if children[i] == op.Child {
@ -76,8 +82,8 @@ func (s *state) Apply(op *Move) error {
}
// do performs a single move operation on a tree.
func (s *state) do(op *Move) LogMove {
lm := LogMove{
func (s *state) do(op *Move) move {
lm := move{
Move: Move{
Parent: op.Parent,
Meta: op.Meta,

View file

@ -36,11 +36,7 @@ type Move struct {
}
// LogMove represents log record for a single move operation.
type LogMove struct {
Move
HasOld bool
Old nodeInfo
}
type LogMove = Move
const (
// RootID represents the ID of a root node.