[Samba] Huge number of small files performance regression from 3.5.16 to 4.6.5 with identical smb.conf

[awl1]

Hello Jeremy,

thanks a million for your help and interest in tracking this down! :-)

Am 13.06.2017 um 18:36 schrieb Jeremy Allison:
> Can you get comparitive wireshark traces for the two cases ?
>
> That would help discover what the bottleneck is.
I am not at all a network guy, but I hope that - maybe with a little 
more help from your part once I have tried to do so in practice - I 
should be able to do so...

Follow-up questions:

Which machine do you want me to run wireshark on? Can this be the 
Windows machine, or will I need to cross-compile a wireshark version to 
run on my NAS first (which might take some days)?

Based on the description here:

     https://wiki.samba.org/index.php/Capture_Packets

I assume that you want me to record ports 139 and 445?

In the first step, I will try and make four records, right:

  * the "write" scenario, copying from Win10 to the NAS with 3.5.16 and
    4.6.5
  * the "read" scenario, copying from the NAS to Win10 with 3.5.16 and 4.6.5

How many files should I copy during each recording?

I'm a little bit worried whether a network trace will indeed pont to the 
root cause, as I fear from looking at smbd CPU usage on the NAS that 
there will be some CPU-bound busy activity (i.e. not just I/O wait) at 
the heart of the issue, but we will hopefully see this during the process.

And finally: Where do you want me to upload the recorded traces to?

Many thanks so far & best regards
Andreas