How to determine the file name involved in an IO operation using windows etw tracing?

I am trying to create a consumer application in vc++, which will collect all disk events using etw tracing at real-time.

I have enabled two flags, the EVENT_TRACE_FLAG_DISK_FILE_IO and the EVENT_TRACE_FLAG_DISK_IO for tracing but the problem is I am not getting as many FileIO_Name events compared to the number of DiskIo_TypeGroup1 events.

But If I only enable the EVENT_TRACE_FLAG_DISK_FILE_IO flag then I am getting more number of FileIO_Name events in my calllback.

FLAG                                          EVENT

EVENT_TRACE_FLAG_DISK_IO                      Enables the following DiskIo event types:
0x00000100                                     DiskIo_TypeGroup1
                                               DiskIo_TypeGroup3

EVENT_TRACE_FLAG_DISK_FILE_IO                 Enables the following FileIo event type:
0x00000200                                    FileIo_Name

I guess I need both the flags because... from the FileIO_Name events I will get FileObject and FileName data and from DiskIO_TypeGroup1 I will get FileObject , DiskNumber , TransferSize and other data's I need to match the common fileobjects to merge both separate data set and get the desired output.

so when I use both flags I get the DiskIO_TypeGroup1:FileObject ratio as 4:1. But when I tweet my code to get only the FileIO_Name event I get 3x times the events that I was getting earlier, if not more.