cmd/sync: use an independent dynamic sync pool (#5568)

pkg/sync/sync.go

@@ -30,7 +30,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/juicedata/juicefs/pkg/chunk"
 	"github.com/juicedata/juicefs/pkg/object"
 	"github.com/juicedata/juicefs/pkg/utils"
 	"github.com/juju/ratelimit"
@@ -553,15 +552,43 @@ func (w *withProgress) Read(b []byte) (int, error) {
 	return n, err
 }
 
+func dynAlloc(size int) []byte {
+	zeros := utils.PowerOf2(size)
+	b := *dynPools[zeros].Get().(*[]byte)
+	if cap(b) < size {
+		panic(fmt.Sprintf("%d < %d", cap(b), size))
+	}
+	return b[:size]
+}
+
+func dynFree(b []byte) {
+	dynPools[utils.PowerOf2(cap(b))].Put(&b)
+}
+
+var dynPools []*sync.Pool
+
+func init() {
+	dynPools = make([]*sync.Pool, 33) // 1 - 8G
+	for i := 0; i < 33; i++ {
+		func(bits int) {
+			dynPools[i] = &sync.Pool{
+				New: func() interface{} {
+					b := make([]byte, 1<<bits)
+					return &b
+				},
+			}
+		}(i)
+	}
+}
+
 func doUploadPart(src, dst object.ObjectStorage, srckey string, off, size int64, key, uploadID string, num int, calChksum bool) (*object.Part, uint32, error) {
 	if limiter != nil {
 		limiter.Wait(size)
 	}
 	start := time.Now()
 	sz := size
-	p := chunk.NewOffPage(int(size))
-	defer p.Release()
-	data := p.Data
+	data := dynAlloc(int(size))
+	defer dynFree(data)
 	var part *object.Part
 	var chksum uint32
 	err := try(3, func() error {

pkg/utils/alloc.go

@@ -28,7 +28,7 @@ var used int64
 
 // Alloc returns size bytes memory from Go heap.
 func Alloc(size int) []byte {
-	zeros := powerOf2(size)
+	zeros := PowerOf2(size)
 	b := *pools[zeros].Get().(*[]byte)
 	if cap(b) < size {
 		panic(fmt.Sprintf("%d < %d", cap(b), size))
@@ -41,7 +41,7 @@ func Alloc(size int) []byte {
 func Free(b []byte) {
 	// buf could be zero length
 	atomic.AddInt64(&used, -int64(cap(b)))
-	pools[powerOf2(cap(b))].Put(&b)
+	pools[PowerOf2(cap(b))].Put(&b)
 }
 
 // AllocMemory returns the allocated memory
@@ -51,7 +51,7 @@ func AllocMemory() int64 {
 
 var pools []*sync.Pool
 
-func powerOf2(s int) int {
+func PowerOf2(s int) int {
 	var bits int
 	var p int = 1
 	for p < s {