Details
Description
XenServer 6.5 and 7.0 did not exhibit this behavior. What I have is XenServer 7.1 in a pool mounted to a CIFS share on a Windows 2012 R2 server. Bandwidth for each server to the share is about 1MB/sec. This seems exactly like what I see. What I see with wireshark is abnormal amounts of "smb echo requests". No changes to samba.conf made any difference so I moved my ISO's to a NFS export and deleted my CIFS Libraries in favor of NFS Libraries.
This ubuntu bug is exactly the sort of thing I am seeing with XenServer.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1686099
--Alan