[Samba] Clients send tons of Notiftication requests

[Rowland penny]

On 11/05/2020 14:52, Luca Marceglia via samba wrote:
> Hi everybody!
>
> I have a QNAP at home running firmware 4.4.2.1273 and I have configured it
> with NFS (for my iMac and FireTV) and SMB access (standalone server, for
> Win10 and iPhone/iPad Files access)
>
> Everything went fine till a certain point where many application would crash
> or behave in a very strange way when accessing SAMBA shares. Application can
> be Explorer++, OneCommander or File.app from my iPhone.
>
>   
>
> What I saw, after a long debugging session, is that these apps send tons of
> Change Notifications requests
>
> smbd_smb2_notify_send: notify change called on ., filter =
> FILE_NAME|DIR_NAME|ATTRIBUTES|CREATION|SECURITY|STREAM_SIZE|STREAM_WRITE,
> recursive = 0
> [2020/05/01 01:32:03.255113, 3]
> ../source3/smbd/smb2_notify.c:253(smbd_smb2_notify_send)
>
I think you are going to have to ask QNAP about this, that is coming 
from this block of code:

     if (DEBUGLEVEL >= 3) {
         char *filter_string;

         filter_string = notify_filter_string(NULL, in_completion_filter);
         if (tevent_req_nomem(filter_string, req)) {
             return tevent_req_post(req, ev);
         }

         DEBUG(3,("smbd_smb2_notify_send: notify change "
              "called on %s, filter = %s, recursive = %d\n",
              fsp_str_dbg(fsp), filter_string, recursive));

         TALLOC_FREE(filter_string);
     }

For Samba to print the message, you would need 'log level = 3' (or 
higher), you have 'log level = 0'

QNAP uses its own version of Samba, so it is possible they have changed 
the code above, or your QNAP is using an old version of Samba.

Rowland