diff --git a/include/libs/monitor/clientMonitor.h b/include/libs/monitor/clientMonitor.h
index abf7df1031..69926c62e5 100644
--- a/include/libs/monitor/clientMonitor.h
+++ b/include/libs/monitor/clientMonitor.h
@@ -38,7 +38,7 @@ typedef enum {
   SLOW_LOG_READ_QUIT = 3,
 } SLOW_LOG_QUEUE_TYPE;
 
-#define SLOW_LOG_SEND_SIZE_MAX 128*1024*1024
+#define SLOW_LOG_SEND_SIZE_MAX 1024*1024
 
 typedef struct {
   int64_t                    clusterId;
diff --git a/source/client/src/clientMonitor.c b/source/client/src/clientMonitor.c
index b603676ee8..9cec7f2d11 100644
--- a/source/client/src/clientMonitor.c
+++ b/source/client/src/clientMonitor.c
@@ -382,6 +382,7 @@ static void monitorWriteSlowLog2File(MonitorSlowLogData* slowLogData, char *tmpP
 }
 
 static char* readFile(TdFilePtr pFile, int64_t *offset, int64_t size){
+  uDebug("[monitor] readFile slow begin pFile:%p, offset:%"PRId64 ", size:%"PRId64, pFile, *offset, size);
   if(taosLSeekFile(pFile, *offset, SEEK_SET) < 0){
     uError("failed to seek file:%p code: %d", pFile, errno);
     return NULL;
@@ -427,7 +428,7 @@ static char* readFile(TdFilePtr pFile, int64_t *offset, int64_t size){
     *offset += (len+1);
   }
 
-  uDebug("[monitor] readFile slow log:%s", pCont);
+  uDebug("[monitor] readFile slow log end, data:%s, offset:%"PRId64, pCont, *offset);
   return pCont;
 }
 
diff --git a/source/client/test/clientMonitorTests.cpp b/source/client/test/clientMonitorTests.cpp
index 6285be5a4c..e0518a2ce2 100644
--- a/source/client/test/clientMonitorTests.cpp
+++ b/source/client/test/clientMonitorTests.cpp
@@ -173,7 +173,7 @@ TEST(clientMonitorTest, ReadOneFile) {
       break;
     }
     char* val = readFile(pFile, &offset, fileSize);
-    printf("offset:%" PRId64",fileSize:%"PRId64",val:%s\n", offset, fileSize, val);
+    printf("offset:%lld,fileSize:%lld,val:%s\n", offset, fileSize, val);
   }
 
 //  char value[size] = {0};