diff --git a/src/configuration.go b/src/configuration.go
index 6117c82..443643a 100644
--- a/src/configuration.go
+++ b/src/configuration.go
@@ -17,7 +17,10 @@ type Configuration struct {
 	HDFSBaseDir            string   `json:"HDFSBaseDir"`
 	DFSBaseDir             string   `json:"DFSBaseDir"`
 	EnableShareRatio       float64  `json:"EnableShareRatio"`
+	ShareMaxUtilization    float64  `json:"ShareMaxUtilization"`
 	EnablePreScheduleRatio float64  `json:"EnablePreScheduleRatio"`
+	PreScheduleExtraTime   int      `json:"PreScheduleExtraTime"` /* seconds to schedule ahead except pre+post */
+	PreScheduleTimeout     int      `json:"PreScheduleTimeout"`
 
 	mock bool
 	mu   sync.Mutex
@@ -46,7 +49,9 @@ func InstanceOfConfiguration() *Configuration {
 			HDFSBaseDir:            "/user/root/",
 			DFSBaseDir:             "",
 			EnableShareRatio:       1.5,
+			ShareMaxUtilization:    1.3, // more than 1.0 to expect more improvement
 			EnablePreScheduleRatio: 1.5,
+			PreScheduleExtraTime:   15,
 		}
 
 		/* override conf value from env */
@@ -84,12 +89,30 @@ func InstanceOfConfiguration() *Configuration {
 				configurationInstance.EnableShareRatio = val
 			}
 		}
+		value = os.Getenv("ShareMaxUtilization")
+		if len(value) != 0 {
+			if val, err := strconv.ParseFloat(value, 32); err == nil {
+				configurationInstance.ShareMaxUtilization = val
+			}
+		}
 		value = os.Getenv("EnablePreScheduleRatio")
 		if len(value) != 0 {
 			if val, err := strconv.ParseFloat(value, 32); err == nil {
 				configurationInstance.EnablePreScheduleRatio = val
 			}
 		}
+		value = os.Getenv("PreScheduleExtraTime")
+		if len(value) != 0 {
+			if val, err := strconv.Atoi(value); err == nil {
+				configurationInstance.PreScheduleExtraTime = val
+			}
+		}
+		value = os.Getenv("PreScheduleTimeout")
+		if len(value) != 0 {
+			if val, err := strconv.Atoi(value); err == nil {
+				configurationInstance.PreScheduleTimeout = val
+			}
+		}
 	}
 	return configurationInstance
 }
@@ -133,6 +156,9 @@ func (config *Configuration) Dump() map[string]interface{} {
 	res["HDFSBaseDir"] = config.HDFSBaseDir
 	res["DFSBaseDir"] = config.DFSBaseDir
 	res["EnableShareRatio"] = config.EnableShareRatio
+	res["ShareMaxUtilization"] = config.ShareMaxUtilization
 	res["EnablePreScheduleRatio"] = config.EnablePreScheduleRatio
+	res["PreScheduleExtraTime"] = config.PreScheduleExtraTime
+	res["PreScheduleTimeout"] = config.PreScheduleTimeout
 	return res
 }
diff --git a/src/job_manager.go b/src/job_manager.go
index 0a5e869..f8909a7 100644
--- a/src/job_manager.go
+++ b/src/job_manager.go
@@ -120,6 +120,8 @@ func (jm *JobManager) start() {
 				resp, err := doRequest("POST", "http://"+jm.resources[index].ClientHost+":8000/create", strings.NewReader(v.Encode()), "application/x-www-form-urlencoded", "")
 				if err != nil {
 					log.Warn(err.Error())
+					jm.job.Status = Failed
+					jm.stop(false)
 					return
 				}
 
@@ -127,6 +129,8 @@ func (jm *JobManager) start() {
 				resp.Body.Close()
 				if err != nil {
 					log.Warn(err)
+					jm.job.Status = Failed
+					jm.stop(false)
 					return
 				}
 
@@ -134,6 +138,8 @@ func (jm *JobManager) start() {
 				err = json.Unmarshal([]byte(string(body)), &res)
 				if err != nil || res.Code != 0 {
 					log.Warn(res)
+					jm.job.Status = Failed
+					jm.stop(false)
 					return
 				}
 				jm.jobStatus.tasks[jm.job.Tasks[index].Name] = TaskStatus{Id: res.Id, Node: jm.resources[index].ClientHost, HostName: jm.job.Tasks[i].Name}
diff --git a/src/resource_pool.go b/src/resource_pool.go
index 71b72d7..4073f74 100644
--- a/src/resource_pool.go
+++ b/src/resource_pool.go
@@ -761,7 +761,7 @@ func (pool *ResourcePool) doAcquireResource(job Job) []NodeStatus {
 								utilT := InstanceOfOptimizer().PredictReq(job, "Worker").UtilGPU
 								totalUtil += utilT
 							}
-							if totalUtil < 100 {
+							if totalUtil < int(InstanceOfConfiguration().ShareMaxUtilization*100) {
 								available = append(available, status)
 							}
 						}
@@ -872,7 +872,7 @@ func (pool *ResourcePool) doAcquireResource(job Job) []NodeStatus {
 							for _, jobT := range jobs {
 								est := InstanceOfOptimizer().PredictTime(jobT)
 								now := time.Now().Unix()
-								if int(now-jobT.StartedAt) > est.Total-est.Post-estimate.Pre-15 {
+								if int(now-jobT.StartedAt) > est.Total-est.Post-estimate.Pre-InstanceOfConfiguration().PreScheduleExtraTime {
 									available = append(available, status)
 								}
 							}