kern/155031: igb(4) DEVICE_POLLING does not work with carp(4)

[Martin Matuska]

>Number:         155031
>Category:       kern
>Synopsis:       igb(4) DEVICE_POLLING does not work with carp(4)
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Feb 25 14:10:11 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Martin Matuska
>Release:        FreeBSD 8.2-RELEASE amd64
>Organization:
VX Solution s. r. o.
>Environment:
>Description:
We are using two redundant load-balancing firewall servers with 4-core Xeon
processors and 2x 4-port igb(4) interfaces using carp(4) for IP failover. 

When DEVICE_POLLING is enabled on the igb(4) interfaces, traffic on these
interfaces stops. After disabling it again traffic continues normally as
before.

The traffic throughput on the desired interface is 100-400 MBit/s.

The CPU load is about 3 (=75%) because of network interrupts.

dev.igb.0.%desc: Intel(R) PRO/1000 Network Connection version - 2.0.7
dev.igb.0.%driver: igb
dev.igb.0.%location: slot=0 function=0
dev.igb.0.%pnpinfo: vendor=0x8086 device=0x10e8 subvendor=0x8086 subdevice=0xa02c class=0x020000

A similar issue was already reported in freebsd-stable mailing list:
http://lists.freebsd.org/pipermail/freebsd-stable/2011-January/061259.html
>How-To-Repeat:
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: