Update goleveldb

Godeps/Godeps.json

@@ -49,7 +49,7 @@
 		},
 		{
 			"ImportPath": "github.com/syndtr/goleveldb/leveldb",
-			"Rev": "6f6f5d93f7499d2c505c2839c1d6b28b25a2ce21"
+			"Rev": "a44c00531ccc005546f20c6e00ab7bb9a8f6b2e0"
 		},
 		{
 			"ImportPath": "github.com/vitrun/qart/coding",

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/bench_test.go

@@ -13,7 +13,6 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
-	"sync/atomic"
 	"testing"
 
 	"github.com/syndtr/goleveldb/leveldb/iterator"
@@ -345,50 +344,6 @@ func BenchmarkDBRead(b *testing.B) {
 	p.close()
 }
 
-func BenchmarkDBReadConcurrent(b *testing.B) {
-	p := openDBBench(b, false)
-	p.populate(b.N)
-	p.fill()
-	p.gc()
-	defer p.close()
-
-	b.ResetTimer()
-	b.SetBytes(116)
-
-	b.RunParallel(func(pb *testing.PB) {
-		iter := p.newIter()
-		defer iter.Release()
-		for pb.Next() && iter.Next() {
-		}
-	})
-}
-
-func BenchmarkDBReadConcurrent2(b *testing.B) {
-	p := openDBBench(b, false)
-	p.populate(b.N)
-	p.fill()
-	p.gc()
-	defer p.close()
-
-	b.ResetTimer()
-	b.SetBytes(116)
-
-	var dir uint32
-	b.RunParallel(func(pb *testing.PB) {
-		iter := p.newIter()
-		defer iter.Release()
-		if atomic.AddUint32(&dir, 1)%2 == 0 {
-			for pb.Next() && iter.Next() {
-			}
-		} else {
-			if pb.Next() && iter.Last() {
-				for pb.Next() && iter.Prev() {
-				}
-			}
-		}
-	})
-}
-
 func BenchmarkDBReadGC(b *testing.B) {
 	p := openDBBench(b, false)
 	p.populate(b.N)

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/db.go

@@ -35,8 +35,8 @@ type DB struct {
 
 	// MemDB.
 	memMu             sync.RWMutex
-	mem               *memdb.DB
-	frozenMem         *memdb.DB
+	memPool           *util.Pool
+	mem, frozenMem    *memDB
 	journal           *journal.Writer
 	journalWriter     storage.Writer
 	journalFile       storage.File
@@ -79,6 +79,8 @@ func openDB(s *session) (*DB, error) {
 		s: s,
 		// Initial sequence
 		seq: s.stSeq,
+		// MemDB
+		memPool: util.NewPool(1),
 		// Write
 		writeC:       make(chan *Batch),
 		writeMergedC: make(chan bool),
@@ -560,19 +562,20 @@ func (db *DB) get(key []byte, seq uint64, ro *opt.ReadOptions) (value []byte, er
 	ikey := newIKey(key, seq, tSeek)
 
 	em, fm := db.getMems()
-	for _, m := range [...]*memdb.DB{em, fm} {
+	for _, m := range [...]*memDB{em, fm} {
 		if m == nil {
 			continue
 		}
+		defer m.decref()
 
-		mk, mv, me := m.Find(ikey)
+		mk, mv, me := m.db.Find(ikey)
 		if me == nil {
 			ukey, _, t, ok := parseIkey(mk)
 			if ok && db.s.icmp.uCompare(ukey, key) == 0 {
 				if t == tDel {
 					return nil, ErrNotFound
 				}
-				return mv, nil
+				return append([]byte{}, mv...), nil
 			}
 		} else if me != ErrNotFound {
 			return nil, me
@@ -592,8 +595,9 @@ func (db *DB) get(key []byte, seq uint64, ro *opt.ReadOptions) (value []byte, er
 // Get gets the value for the given key. It returns ErrNotFound if the
 // DB does not contain the key.
 //
-// The caller should not modify the contents of the returned slice, but
-// it is safe to modify the contents of the argument after Get returns.
+// The returned slice is its own copy, it is safe to modify the contents
+// of the returned slice.
+// It is safe to modify the contents of the argument after Get returns.
 func (db *DB) Get(key []byte, ro *opt.ReadOptions) (value []byte, err error) {
 	err = db.ok()
 	if err != nil {

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/db_compaction.go

@@ -216,14 +216,15 @@ func (db *DB) memCompaction() {
 	if mem == nil {
 		return
 	}
+	defer mem.decref()
 
 	c := newCMem(db.s)
 	stats := new(cStatsStaging)
 
-	db.logf("mem@flush N·%d S·%s", mem.Len(), shortenb(mem.Size()))
+	db.logf("mem@flush N·%d S·%s", mem.db.Len(), shortenb(mem.db.Size()))
 
 	// Don't compact empty memdb.
-	if mem.Len() == 0 {
+	if mem.db.Len() == 0 {
 		db.logf("mem@flush skipping")
 		// drop frozen mem
 		db.dropFrozenMem()
@@ -241,7 +242,7 @@ func (db *DB) memCompaction() {
 	db.compactionTransact("mem@flush", func(cnt *compactionTransactCounter) (err error) {
 		stats.startTimer()
 		defer stats.stopTimer()
-		return c.flush(mem, -1)
+		return c.flush(mem.db, -1)
 	}, func() error {
 		for _, r := range c.rec.addedTables {
 			db.logf("mem@flush rollback @%d", r.num)

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/db_iter.go

@@ -9,6 +9,7 @@ package leveldb
 import (
 	"errors"
 	"runtime"
+	"sync"
 
 	"github.com/syndtr/goleveldb/leveldb/iterator"
 	"github.com/syndtr/goleveldb/leveldb/opt"
@@ -19,6 +20,17 @@ var (
 	errInvalidIkey = errors.New("leveldb: Iterator: invalid internal key")
 )
 
+type memdbReleaser struct {
+	once sync.Once
+	m    *memDB
+}
+
+func (mr *memdbReleaser) Release() {
+	mr.once.Do(func() {
+		mr.m.decref()
+	})
+}
+
 func (db *DB) newRawIterator(slice *util.Range, ro *opt.ReadOptions) iterator.Iterator {
 	em, fm := db.getMems()
 	v := db.s.version()
@@ -26,9 +38,13 @@ func (db *DB) newRawIterator(slice *util.Range, ro *opt.ReadOptions) iterator.It
 	ti := v.getIterators(slice, ro)
 	n := len(ti) + 2
 	i := make([]iterator.Iterator, 0, n)
-	i = append(i, em.NewIterator(slice))
+	emi := em.db.NewIterator(slice)
+	emi.SetReleaser(&memdbReleaser{m: em})
+	i = append(i, emi)
 	if fm != nil {
-		i = append(i, fm.NewIterator(slice))
+		fmi := fm.db.NewIterator(slice)
+		fmi.SetReleaser(&memdbReleaser{m: fm})
+		i = append(i, fmi)
 	}
 	i = append(i, ti...)
 	strict := db.s.o.GetStrict(opt.StrictIterator) || ro.GetStrict(opt.StrictIterator)

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/db_state.go

@@ -11,8 +11,27 @@ import (
 
 	"github.com/syndtr/goleveldb/leveldb/journal"
 	"github.com/syndtr/goleveldb/leveldb/memdb"
+	"github.com/syndtr/goleveldb/leveldb/util"
 )
 
+type memDB struct {
+	pool *util.Pool
+	db   *memdb.DB
+	ref  int32
+}
+
+func (m *memDB) incref() {
+	atomic.AddInt32(&m.ref, 1)
+}
+
+func (m *memDB) decref() {
+	if ref := atomic.AddInt32(&m.ref, -1); ref == 0 {
+		m.pool.Put(m)
+	} else if ref < 0 {
+		panic("negative memdb ref")
+	}
+}
+
 // Get latest sequence number.
 func (db *DB) getSeq() uint64 {
 	return atomic.LoadUint64(&db.seq)
@@ -25,7 +44,7 @@ func (db *DB) addSeq(delta uint64) {
 
 // Create new memdb and froze the old one; need external synchronization.
 // newMem only called synchronously by the writer.
-func (db *DB) newMem(n int) (mem *memdb.DB, err error) {
+func (db *DB) newMem(n int) (mem *memDB, err error) {
 	num := db.s.allocFileNum()
 	file := db.s.getJournalFile(num)
 	w, err := file.Create()
@@ -37,6 +56,10 @@ func (db *DB) newMem(n int) (mem *memdb.DB, err error) {
 	db.memMu.Lock()
 	defer db.memMu.Unlock()
 
+	if db.frozenMem != nil {
+		panic("still has frozen mem")
+	}
+
 	if db.journal == nil {
 		db.journal = journal.NewWriter(w)
 	} else {
@@ -47,8 +70,19 @@ func (db *DB) newMem(n int) (mem *memdb.DB, err error) {
 	db.journalWriter = w
 	db.journalFile = file
 	db.frozenMem = db.mem
-	db.mem = memdb.New(db.s.icmp, maxInt(db.s.o.GetWriteBuffer(), n))
-	mem = db.mem
+	mem, ok := db.memPool.Get().(*memDB)
+	if ok && mem.db.Capacity() >= n {
+		mem.db.Reset()
+		mem.incref()
+	} else {
+		mem = &memDB{
+			pool: db.memPool,
+			db:   memdb.New(db.s.icmp, maxInt(db.s.o.GetWriteBuffer(), n)),
+			ref:  1,
+		}
+	}
+	mem.incref()
+	db.mem = mem
 	// The seq only incremented by the writer. And whoever called newMem
 	// should hold write lock, so no need additional synchronization here.
 	db.frozenSeq = db.seq
@@ -56,16 +90,27 @@ func (db *DB) newMem(n int) (mem *memdb.DB, err error) {
 }
 
 // Get all memdbs.
-func (db *DB) getMems() (e *memdb.DB, f *memdb.DB) {
+func (db *DB) getMems() (e, f *memDB) {
 	db.memMu.RLock()
 	defer db.memMu.RUnlock()
+	if db.mem == nil {
+		panic("nil effective mem")
+	}
+	db.mem.incref()
+	if db.frozenMem != nil {
+		db.frozenMem.incref()
+	}
 	return db.mem, db.frozenMem
 }
 
 // Get frozen memdb.
-func (db *DB) getEffectiveMem() *memdb.DB {
+func (db *DB) getEffectiveMem() *memDB {
 	db.memMu.RLock()
 	defer db.memMu.RUnlock()
+	if db.mem == nil {
+		panic("nil effective mem")
+	}
+	db.mem.incref()
 	return db.mem
 }
 
@@ -77,9 +122,12 @@ func (db *DB) hasFrozenMem() bool {
 }
 
 // Get frozen memdb.
-func (db *DB) getFrozenMem() *memdb.DB {
+func (db *DB) getFrozenMem() *memDB {
 	db.memMu.RLock()
 	defer db.memMu.RUnlock()
+	if db.frozenMem != nil {
+		db.frozenMem.incref()
+	}
 	return db.frozenMem
 }
 
@@ -92,6 +140,7 @@ func (db *DB) dropFrozenMem() {
 		db.logf("journal@remove removed @%d", db.frozenJournalFile.Num())
 	}
 	db.frozenJournalFile = nil
+	db.frozenMem.decref()
 	db.frozenMem = nil
 	db.memMu.Unlock()
 }

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/db_write.go

@@ -45,7 +45,7 @@ func (db *DB) jWriter() {
 	}
 }
 
-func (db *DB) rotateMem(n int) (mem *memdb.DB, err error) {
+func (db *DB) rotateMem(n int) (mem *memDB, err error) {
 	// Wait for pending memdb compaction.
 	err = db.compSendIdle(db.mcompCmdC)
 	if err != nil {
@@ -63,13 +63,19 @@ func (db *DB) rotateMem(n int) (mem *memdb.DB, err error) {
 	return
 }
 
-func (db *DB) flush(n int) (mem *memdb.DB, nn int, err error) {
+func (db *DB) flush(n int) (mem *memDB, nn int, err error) {
 	delayed := false
-	flush := func() bool {
+	flush := func() (retry bool) {
 		v := db.s.version()
 		defer v.release()
 		mem = db.getEffectiveMem()
-		nn = mem.Free()
+		defer func() {
+			if retry {
+				mem.decref()
+				mem = nil
+			}
+		}()
+		nn = mem.db.Free()
 		switch {
 		case v.tLen(0) >= kL0_SlowdownWritesTrigger && !delayed:
 			delayed = true
@@ -84,12 +90,17 @@ func (db *DB) flush(n int) (mem *memdb.DB, nn int, err error) {
 			}
 		default:
 			// Allow memdb to grow if it has no entry.
-			if mem.Len() == 0 {
+			if mem.db.Len() == 0 {
 				nn = n
-				return false
+			} else {
+				mem.decref()
+				mem, err = db.rotateMem(n)
+				if err == nil {
+					nn = mem.db.Free()
+				} else {
+					nn = 0
+				}
 			}
-			mem, err = db.rotateMem(n)
-			nn = mem.Free()
 			return false
 		}
 		return true
@@ -140,6 +151,7 @@ retry:
 	if err != nil {
 		return
 	}
+	defer mem.decref()
 
 	// Calculate maximum size of the batch.
 	m := 1 << 20
@@ -178,7 +190,7 @@ drain:
 			return
 		case db.journalC <- b:
 			// Write into memdb
-			b.memReplay(mem)
+			b.memReplay(mem.db)
 		}
 		// Wait for journal writer
 		select {
@@ -188,7 +200,7 @@ drain:
 		case err = <-db.journalAckC:
 			if err != nil {
 				// Revert memdb if error detected
-				b.revertMemReplay(mem)
+				b.revertMemReplay(mem.db)
 				return
 			}
 		}
@@ -197,7 +209,7 @@ drain:
 		if err != nil {
 			return
 		}
-		b.memReplay(mem)
+		b.memReplay(mem.db)
 	}
 
 	// Set last seq number.
@@ -258,7 +270,8 @@ func (db *DB) CompactRange(r util.Range) error {
 
 	// Check for overlaps in memdb.
 	mem := db.getEffectiveMem()
-	if isMemOverlaps(db.s.icmp, mem, r.Start, r.Limit) {
+	defer mem.decref()
+	if isMemOverlaps(db.s.icmp, mem.db, r.Start, r.Limit) {
 		// Memdb compaction.
 		if _, err := db.rotateMem(0); err != nil {
 			<-db.writeLockC

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/go13_bench_test.go

@@ -0,0 +1,58 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build go1.3
+
+package leveldb
+
+import (
+	"sync/atomic"
+	"testing"
+)
+
+func BenchmarkDBReadConcurrent(b *testing.B) {
+	p := openDBBench(b, false)
+	p.populate(b.N)
+	p.fill()
+	p.gc()
+	defer p.close()
+
+	b.ResetTimer()
+	b.SetBytes(116)
+
+	b.RunParallel(func(pb *testing.PB) {
+		iter := p.newIter()
+		defer iter.Release()
+		for pb.Next() && iter.Next() {
+		}
+	})
+}
+
+func BenchmarkDBReadConcurrent2(b *testing.B) {
+	p := openDBBench(b, false)
+	p.populate(b.N)
+	p.fill()
+	p.gc()
+	defer p.close()
+
+	b.ResetTimer()
+	b.SetBytes(116)
+
+	var dir uint32
+	b.RunParallel(func(pb *testing.PB) {
+		iter := p.newIter()
+		defer iter.Release()
+		if atomic.AddUint32(&dir, 1)%2 == 0 {
+			for pb.Next() && iter.Next() {
+			}
+		} else {
+			if pb.Next() && iter.Last() {
+				for pb.Next() && iter.Prev() {
+				}
+			}
+		}
+	})
+}

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/util/buffer_pool.go

@@ -4,6 +4,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+// +build go1.3
+
 package util
 
 import (

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/util/buffer_pool_legacy.go

@@ -0,0 +1,143 @@
+// Copyright (c) 2014, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build !go1.3
+
+package util
+
+import (
+	"fmt"
+	"sync/atomic"
+)
+
+type buffer struct {
+	b    []byte
+	miss int
+}
+
+// BufferPool is a 'buffer pool'.
+type BufferPool struct {
+	pool      [4]chan []byte
+	size      [3]uint32
+	sizeMiss  [3]uint32
+	baseline0 int
+	baseline1 int
+	baseline2 int
+
+	less    uint32
+	equal   uint32
+	greater uint32
+	miss    uint32
+}
+
+func (p *BufferPool) poolNum(n int) int {
+	switch {
+	case n <= p.baseline0:
+		return 0
+	case n <= p.baseline1:
+		return 1
+	case n <= p.baseline2:
+		return 2
+	default:
+		return 3
+	}
+}
+
+// Get returns buffer with length of n.
+func (p *BufferPool) Get(n int) []byte {
+	poolNum := p.poolNum(n)
+	pool := p.pool[poolNum]
+	if poolNum == 0 {
+		// Fast path.
+		select {
+		case b := <-pool:
+			switch {
+			case cap(b) > n:
+				atomic.AddUint32(&p.less, 1)
+				return b[:n]
+			case cap(b) == n:
+				atomic.AddUint32(&p.equal, 1)
+				return b[:n]
+			default:
+				panic("not reached")
+			}
+		default:
+			atomic.AddUint32(&p.miss, 1)
+		}
+
+		return make([]byte, n, p.baseline0)
+	} else {
+		sizePtr := &p.size[poolNum-1]
+
+		select {
+		case b := <-pool:
+			switch {
+			case cap(b) > n:
+				atomic.AddUint32(&p.less, 1)
+				return b[:n]
+			case cap(b) == n:
+				atomic.AddUint32(&p.equal, 1)
+				return b[:n]
+			default:
+				atomic.AddUint32(&p.greater, 1)
+				if uint32(cap(b)) >= atomic.LoadUint32(sizePtr) {
+					select {
+					case pool <- b:
+					default:
+					}
+				}
+			}
+		default:
+			atomic.AddUint32(&p.miss, 1)
+		}
+
+		if size := atomic.LoadUint32(sizePtr); uint32(n) > size {
+			if size == 0 {
+				atomic.CompareAndSwapUint32(sizePtr, 0, uint32(n))
+			} else {
+				sizeMissPtr := &p.sizeMiss[poolNum-1]
+				if atomic.AddUint32(sizeMissPtr, 1) == 20 {
+					atomic.StoreUint32(sizePtr, uint32(n))
+					atomic.StoreUint32(sizeMissPtr, 0)
+				}
+			}
+			return make([]byte, n)
+		} else {
+			return make([]byte, n, size)
+		}
+	}
+}
+
+// Put adds given buffer to the pool.
+func (p *BufferPool) Put(b []byte) {
+	pool := p.pool[p.poolNum(cap(b))]
+	select {
+	case pool <- b:
+	default:
+	}
+
+}
+
+func (p *BufferPool) String() string {
+	return fmt.Sprintf("BufferPool{B·%d Z·%v Zm·%v L·%d E·%d G·%d M·%d}",
+		p.baseline0, p.size, p.sizeMiss, p.less, p.equal, p.greater, p.miss)
+}
+
+// NewBufferPool creates a new initialized 'buffer pool'.
+func NewBufferPool(baseline int) *BufferPool {
+	if baseline <= 0 {
+		panic("baseline can't be <= 0")
+	}
+	p := &BufferPool{
+		baseline0: baseline,
+		baseline1: baseline * 2,
+		baseline2: baseline * 4,
+	}
+	for i, cap := range []int{6, 6, 3, 1} {
+		p.pool[i] = make(chan []byte, cap)
+	}
+	return p
+}

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/util/pool.go

@@ -0,0 +1,21 @@
+// Copyright (c) 2014, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build go1.3
+
+package util
+
+import (
+	"sync"
+)
+
+type Pool struct {
+	sync.Pool
+}
+
+func NewPool(cap int) *Pool {
+	return &Pool{}
+}

Godeps/_workspace/src/github.com/syndtr/goleveldb/leveldb/util/pool_legacy.go

@@ -0,0 +1,33 @@
+// Copyright (c) 2014, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// +build !go1.3
+
+package util
+
+type Pool struct {
+	pool chan interface{}
+}
+
+func (p *Pool) Get() interface{} {
+	select {
+	case x := <-p.pool:
+		return x
+	default:
+		return nil
+	}
+}
+
+func (p *Pool) Put(x interface{}) {
+	select {
+	case p.pool <- x:
+	default:
+	}
+}
+
+func NewPool(cap int) *Pool {
+	return &Pool{pool: make(chan interface{}, cap)}
+}