minor changes

source/dnode/mnode/impl/src/mnode.c

@@ -533,6 +533,8 @@ void mndGetLoad(SMnode *pMnode, SMnodeLoad *pLoad) {
 
 int32_t mndGetMonitorInfo(SMnode *pMnode, SMonClusterInfo *pClusterInfo, SMonVgroupInfo *pVgroupInfo,
                           SMonGrantInfo *pGrantInfo) {
+  if (!mndIsMaster(pMnode)) return;
+
   SSdb   *pSdb = pMnode->pSdb;
   int64_t ms = taosGetTimestampMs();
 

source/os/src/osSysinfo.c

@@ -539,7 +539,7 @@ int32_t taosGetDiskSize(char *dataDir, SDiskSize *diskSize) {
   } else {
     diskSize->total = info.f_blocks * info.f_frsize;
     diskSize->avail = info.f_bavail * info.f_frsize;
-    diskSize->used = (info.f_blocks - info.f_bfree) * info.f_frsize;
+    diskSize->used = diskSize->total - diskSize->avail;
     return 0;
   }
 }