diff --git a/src/cm_server/cms_alarm.cpp b/src/cm_server/cms_alarm.cpp
index 3c877fb6b98e99584bb3ff5ee7aa3a0c79b38e75..cdc9e5b3ff20dd1e9f09ddc2d16a6c4360170ef9 100644
--- a/src/cm_server/cms_alarm.cpp
+++ b/src/cm_server/cms_alarm.cpp
@@ -58,7 +58,7 @@ void ReportCMSAlarmNormalCluster(Alarm* alarmItem, AlarmType type, AlarmAddition
 
 void ReadOnlyAlarmItemInitialize(void)
 {
-    uint32 readOnlyCount = MAX_CN_NUM + MAX_DN_NUM;
+    uint32 readOnlyCount = MAX_DN_NUM;
     g_readOnlyAlarm = (InstanceAlarm*)malloc(sizeof(InstanceAlarm) * readOnlyCount);
     g_readOnlyPreAlarm = (InstanceAlarm*)malloc(sizeof(InstanceAlarm) * readOnlyCount);
     g_logStorageAlarm = (Alarm*)malloc(sizeof(Alarm) * CM_NODE_MAXNUM);
@@ -99,7 +99,7 @@ void ReadOnlyAlarmItemInitialize(void)
 
 void ReportReadOnlyAlarm(AlarmType alarmType, const char* instanceName, uint32 instanceid)
 {
-    uint32 readOnlyCount = MAX_CN_NUM + MAX_DN_NUM;
+    uint32 readOnlyCount = MAX_DN_NUM;
     uint32 alarmIndex = 0;
     for (; alarmIndex < readOnlyCount; alarmIndex++) {
         if (instanceid == g_readOnlyAlarm[alarmIndex].instanceId) {
@@ -123,7 +123,7 @@ void ReportReadOnlyAlarm(AlarmType alarmType, const char* instanceName, uint32 i
 
 void ReportReadOnlyPreAlarm(AlarmType alarmType, const char* instanceName, uint32 instanceid)
 {
-    uint32 readOnlyCount = MAX_CN_NUM + MAX_DN_NUM;
+    uint32 readOnlyCount = MAX_DN_NUM;
     uint32 alarmIndex = 0;
     for (; alarmIndex < readOnlyCount; alarmIndex++) {
         if (instanceid == g_readOnlyPreAlarm[alarmIndex].instanceId) {
@@ -225,7 +225,7 @@ void InstanceAlarmItemInitialize(void)
     }
     g_instance_count = (int)(g_coordinator_num + g_gtm_num + dn_count);
     if (g_instance_count > MAX_INSTANCE_NUM) {
-        write_runlog(ERROR, "total instance count %d is greater than max(2048).\n", g_instance_count);
+        write_runlog(ERROR, "total instance count %d is greater than max(%d).\n", g_instance_count, MAX_INSTANCE_NUM);
         return;
     }
     g_phony_dead_alarm = (InstancePhonyDeadAlarm *)malloc(sizeof(InstancePhonyDeadAlarm) * MAX_INSTANCE_NUM);
@@ -246,7 +246,7 @@ void InstanceAlarmItemInitialize(void)
         for (int32 j = 0; j < g_instance_role_group_ptr[i].count; j++) {
             uint32 instanceid = g_instance_role_group_ptr[i].instanceMember[j].instanceId;
             if (alarmIndex >= MAX_INSTANCE_NUM) {
-                write_runlog(ERROR, "out of range 2048.\n");
+                write_runlog(ERROR, "out of range %d.\n", MAX_INSTANCE_NUM);
                 return;
             }
 
diff --git a/src/include/cm/cm_server/cms_global_params.h b/src/include/cm/cm_server/cms_global_params.h
index 78ce60f4a11199b706eb62abbb5061c77651ba57..444b6961a948764d2b6401ecf0ea723097c42fc3 100644
--- a/src/include/cm/cm_server/cms_global_params.h
+++ b/src/include/cm/cm_server/cms_global_params.h
@@ -234,8 +234,8 @@ typedef enum ThreadProcessStatusE {
 
 #define AUTHENTICATION_TIMEOUT 60
 #define RELOADWAIT_TIMEOUT 60
-#define MAX_DN_NUM 1024
-#define MAX_INSTANCE_NUM 2048
+#define MAX_DN_NUM 9
+#define MAX_INSTANCE_NUM 9
 
 #define CAN_NOT_SEND_SYNC_lIST 1
 #define NOT_NEED_TO_SEND_SYNC_LIST 2
diff --git a/src/include/opengauss/common/config/cm_config.h b/src/include/opengauss/common/config/cm_config.h
index 4e690cd53043b7306ba958229bf704e5930a95b1..c6290d50c217f869b388c411277497c99b8d079d 100644
--- a/src/include/opengauss/common/config/cm_config.h
+++ b/src/include/opengauss/common/config/cm_config.h
@@ -39,10 +39,10 @@
 #define CM_IP_LENGTH 128
 #define CM_IP_ALL_NUM_LENGTH (CM_IP_NUM * CM_IP_LENGTH)
 #define CM_PATH_LENGTH 1024
-#define CM_NODE_MAXNUM 1024
-#define CM_MAX_DATANODE_PER_NODE 160
+#define CM_NODE_MAXNUM 9
+#define CM_MAX_DATANODE_PER_NODE 9
 #define CM_MAX_THREAD_NUM (165)
-#define CM_MAX_INSTANCE_PER_NODE 192
+#define CM_MAX_INSTANCE_PER_NODE 9
 #define INVALID_NODE_NUM (CM_NODE_MAXNUM + 1)
 #define INVALID_INSTACNE_NUM (0xFFFFFFFF)
 #define CM_MAX_INSTANCE_GROUP_NUM (CM_NODE_MAXNUM * CM_MAX_INSTANCE_PER_NODE)
@@ -67,7 +67,7 @@
 #endif
 
 #define CM_MAX_GTM_STANDBY_NUM (7)
-#define MAX_CN_NUM 256
+#define MAX_CN_NUM 9
 #define CM_MAX_SQL_COMMAND_LEN 2048
 
 #define HAVE_GTM 1