FreeBSD 11.1-R network slowness on Samba

[Terry Kennedy]

> Then I updated to 11.1-R by recompiling from svn, using the same
> kernelconfig from 10.3, and now my windows client shows timeouts and
> really slow connection. File copy never past kilobytes per second :(

  I think the issue is with the SAMBA port. I was running the samba36
port under FreeBSD 10.x and things were fine (500Mbyte/sec transfers
using 10GbE). At some point the samba36 port broke due to changes in
one or more of talloc/tdb/tevent and I tried various samba4x ports (I
am using samba44 now, samba46 doesn't seem to work with XP-type client
systems).

  Various directory traversal operations spike the CPU load up to 100%
and clients see very bursty behavior. A lot seems to depend on the 
application in use - my benchmark is clrmamepro:
https://mamedev.emulab.it/clrmamepro/

  But even things like Windows (7) Photo Viewer will just sit at the
"Loading..." message for a random length of time before displaying
the next picture.

  I am seeing easily a 10:1 performance degradation with any of the 
samba4x ports. I have tried large numbers of SAMBA config tuning
changes, different port build options, etc. without any success. I
"solved" the problem by using an old FreeBSD 8.4 box with a 10GbE
card as an NFS client to the storage server, and then exporting the
NFS-mounted storage to clients with samba36. This whole chain is
nearly as fast as the old samba36-on-storage-server setup.

  I may try resurrecting the samba36 port under FreeBSD 11.1 to see
if that has the performance I used to get. I'm not sure how hard
it will be to build samba36, though. Things have changed since the
port was retired.

        Terry Kennedy     http://www.glaver.org      New York, NY USA