[svlug] Network performance on CentOS 7

[Michael Eager]

I have set up a ZFS file server with CentOS 7.  I'm seeing
network performance which is considerably slower than a similar
server running CentOS 6.6 with ext4.  A 3Gb directory can be
copied to/from the CentOS 6.6 server in about 50 seconds.  The
same directory takes about 270 seconds to copy to/from the CentOS
7 system.

I see the same performance difference with NFS mounted file
systems or using scp, so it doesn't appear to be an NFS or
ZFS issue.  The MTU on the NICs on both systems is 1500, and
changing it to 6000 on the CentOS 7 system had no effect.
I've confirmed that both NICs are running at 1GigE.

Anyone have any ideas what might cause this problem, how to
track it down, or how to fix it?

-- 
Michael Eager	 eager at eagercon.com
1960 Park Blvd., Palo Alto, CA 94306  650-325-8077