add btree for volume index

weed/storage/needle/compact_map_perf_test.go

@@ -0,0 +1,44 @@
+package needle
+
+import (
+	"log"
+	"os"
+	"testing"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+func TestMemoryUsage(t *testing.T) {
+
+	indexFile, ie := os.OpenFile("../../../test/sample.idx", os.O_RDWR|os.O_RDONLY, 0644)
+	if ie != nil {
+		log.Fatalln(ie)
+	}
+	loadNewNeedleMap(indexFile)
+
+}
+
+func loadNewNeedleMap(file *os.File) {
+	m := NewCompactMap()
+	bytes := make([]byte, 16*1024)
+	count, e := file.Read(bytes)
+	if count > 0 {
+		fstat, _ := file.Stat()
+		glog.V(0).Infoln("Loading index file", fstat.Name(), "size", fstat.Size())
+	}
+	for count > 0 && e == nil {
+		for i := 0; i < count; i += 16 {
+			key := util.BytesToUint64(bytes[i : i+8])
+			offset := util.BytesToUint32(bytes[i+8 : i+12])
+			size := util.BytesToUint32(bytes[i+12 : i+16])
+			if offset > 0 {
+				m.Set(Key(key), offset, size)
+			} else {
+				//delete(m, key)
+			}
+		}
+
+		count, e = file.Read(bytes)
+	}
+}