diff --git a/ceph-gobench.go b/ceph-gobench.go
index 45df3ec..0a5955b 100644
--- a/ceph-gobench.go
+++ b/ceph-gobench.go
@@ -13,25 +13,7 @@ import (
 	"time"
 )
 
-//future feature
-func makeoffsets(threads int64, bs int64, objsize int64) [][]int64 {
-	var offsets [][]int64
-	for i := int64(0); i < threads; i++ {
-		s1 := rand.NewSource(i)
-		r1 := rand.New(s1)
-		localoffsets := make([]int64, 0, objsize-bs)
-		for i := int64(0); i < objsize-bs; i += bs {
-			localoffsets = append(localoffsets, i)
-		}
-		r1.Shuffle(len(localoffsets), func(i, j int) {
-			localoffsets[i], localoffsets[j] = localoffsets[j], localoffsets[i]
-		})
-		offsets = append(offsets, localoffsets)
-	}
-	return offsets
-}
-
-func bench(cephconn *Cephconnection, osddevice Device, buffs *[][]byte, offset [][]int64, params *Params,
+func bench(cephconn *Cephconnection, osddevice Device, buffs *[][]byte, bs int64, objsize int64, params *Params,
 	wg *sync.WaitGroup, result chan string) {
 	defer wg.Done()
 	threadresult := make(chan []time.Duration, params.threadsCount)
@@ -43,14 +25,14 @@ func bench(cephconn *Cephconnection, osddevice Device, buffs *[][]byte, offset [
 		}
 	}()
 	// calculate object for each thread
-	for suffix := 0; len(objectnames) < int(params.threadsCount); suffix++ {
+	for suffix := 0; len(objectnames) < int(params.threadsCount)*16; suffix++ {
 		name := "bench_" + strconv.Itoa(suffix)
 		if osddevice.ID == GetObjActingPrimary(cephconn, *params, name) {
 			objectnames = append(objectnames, name)
 		}
 	}
-	for i, j := 0, 0; i < int(params.threadsCount); i, j = i+1, j+2 {
-		go bench_thread(cephconn, osddevice, (*buffs)[j:j+2], offset[i], params, threadresult, objectnames[i])
+	for i := 0; i < int(params.threadsCount); i++ {
+		go bench_thread(cephconn, osddevice, (*buffs)[i*2:i*2+2], bs, objsize, params, threadresult, objectnames[i*16:i*16+16])
 	}
 	for i := int64(0); i < params.threadsCount; i++ {
 		for _, lat := range <-threadresult {
@@ -131,31 +113,27 @@ func bench(cephconn *Cephconnection, osddevice Device, buffs *[][]byte, offset [
 	result <- buffer.String()
 }
 
-func bench_thread(cephconn *Cephconnection, osddevice Device, buffs [][]byte, offsets []int64, params *Params,
-	result chan []time.Duration, objname string) {
+func bench_thread(cephconn *Cephconnection, osddevice Device, buffs [][]byte, bs int64, objsize int64, params *Params,
+	result chan []time.Duration, objnames []string) {
 
 	starttime := time.Now()
 	var latencies []time.Duration
 	endtime := starttime.Add(params.duration)
 	n := 0
 	for {
-		if time.Now().After(endtime) {
+		offset := rand.Int63n(objsize/bs) * bs
+		objname := objnames[rand.Int31n(int32(len(objnames)))]
+		startwritetime := time.Now()
+		if startwritetime.After(endtime) {
 			break
 		}
-		for _, offset := range offsets {
-			if time.Now().Before(endtime) {
-				startwritetime := time.Now()
-				err := cephconn.ioctx.Write(objname, buffs[n], uint64(offset))
-				endwritetime := time.Now()
-				if err != nil {
-					log.Printf("Can't write obj: %v, osd: %v", objname, osddevice.Name)
-					continue
-				}
-				latencies = append(latencies, endwritetime.Sub(startwritetime))
-			} else {
-				break
-			}
+		err := cephconn.ioctx.Write(objname, buffs[n], uint64(offset))
+		endwritetime := time.Now()
+		if err != nil {
+			log.Printf("Can't write obj: %v, osd: %v", objname, osddevice.Name)
+			continue
 		}
+		latencies = append(latencies, endwritetime.Sub(startwritetime))
 		if n == 0 {
 			n++
 		} else {
@@ -184,16 +162,15 @@ func main() {
 		}
 	}
 	osddevices := GetOsds(cephconn, params)
-	offsets := makeoffsets(params.threadsCount, params.blocksize, params.objectsize)
 
 	var wg sync.WaitGroup
 	results := make(chan string, len(osddevices)*int(params.threadsCount))
 	for _, osd := range osddevices {
 		wg.Add(1)
 		if params.parallel == true {
-			go bench(cephconn, osd, &buffs, offsets, &params, &wg, results)
+			go bench(cephconn, osd, &buffs, params.blocksize, params.objectsize, &params, &wg, results)
 		} else {
-			bench(cephconn, osd, &buffs, offsets, &params, &wg, results)
+			bench(cephconn, osd, &buffs, params.blocksize, params.objectsize, &params, &wg, results)
 			log.Println(<-results)
 		}