Bug 65261

Summary: Packet loss or excessive packet delay repeatedly for some seconds
Product: Networking Reporter: Arno Wagner (arno)
Component: IPV4Assignee: Stephen Hemminger (stephen)
Status: RESOLVED DUPLICATE    
Severity: high CC: alan
Priority: P1    
Hardware: x86-64   
OS: Linux   
See Also: https://bugzilla.kernel.org/show_bug.cgi?id=64981
Kernel Version: 3.10.19 Subsystem:
Regression: No Bisected commit-id:
Attachments: Kernel config 3.10.19

Description Arno Wagner 2013-11-20 13:57:50 UTC
Created attachment 115261 [details]
Kernel config 3.10.19

I recently upgraded my development-server/firewall/NAT-box from 3.10.17 to 3.10.19. Since then I noticed increased DNS lookup failures on a connected Windows box and occasional slow updates on putty-SSH logins when scrolling in an editor (joe, takes something like an estimated 100-300ms for screen updates). These update delays are repeatable for something like 10-20 seconds or more, e.g. inserting a line and then deleting again, then vanish. The delays make remote editing hard to do when they happen. The DNS lookup failures are really annoying. 

I have not found a way to reliably trigger the problem.

Going back to 3.10.17 fixed the issue as far as I can tell. (Several hours editing source code without it showing up.) The only change between the two configurations was that I added the scsi CDROM driver (which should not be able to cause this?).

The network connection has an iptables "all pass" on the server side for the affected connection. The client side is a Win7 machine. The network link is GbE with 2 Switches in there. No packet loss on ping/ping -f. Network hardware is  Intel 82574L Gigabit card on both sides.
Comment 1 Alan 2013-11-26 22:14:32 UTC
This is really useful as it matches another strange bug. The other person did a git bisect and found the problem appeared to be om 3.10.18

https://bugzilla.kernel.org/show_bug.cgi?id=64981

I don't know if you can test 3.10.18 or the bisection point but it would be most interesting to confirm.
Comment 2 Arno Wagner 2013-11-27 04:49:53 UTC
I can test 3.10.18, no problem. Might take a few days though. I am not sure I currently have the skills with git to test the bisection point, but if my issue turns up with 3.10.18, I am willing to try.
Comment 3 Alan 2013-11-27 11:50:54 UTC
No need.. Eric things is probably fixed and heading for the stable kernels

*** This bug has been marked as a duplicate of bug 64981 ***
Comment 4 Arno Wagner 2013-11-27 13:55:32 UTC
Thanks, I will just wait for 3.10.21.