em performs worse than igb (latency wise) in 12?

Pete French petefrench at ingresso.co.uk
Fri Apr 5 18:57:03 UTC 2019

On 05/04/2019 16:01, Kris von Mach wrote:
> I've upgraded from Stable 11 to Stable 12, and noticed that igb has been
> removed and is now part of em driver. However, the performance seems a
> lot worse. This is using HP 366FLR which is just HP's version of Intel
> i350 I believe.

Something odd going on there there - I am using 12-STABLE and I have igb 
just fine, and it attaches to the same hardware that 11 did:


[petefrench at dilbert ~]$ ssh turpentine
Last login: Fri Apr  5 18:52:50 2019 from 2a02:b90:3002:411::6
FreeBSD 12.0-STABLE r343538 GENERIC

Baby baby turpentine...

[webadmin at turpentine ~]$ ifconfig igb0
igb0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether ac:1f:6b:46:5e:32
	inet netmask 0xffff0000 broadcast
	inet6 fe80::ae1f:6bff:fe46:5e32%igb0 prefixlen 64 scopeid 0x1
	inet6 2a02:1658:1:2:e550::5 prefixlen 64
	media: Ethernet autoselect (1000baseT <full-duplex>)
	status: active

Do you have a custom kernel, and if so did you see this note in UPDATING?

         The igb(4), em(4) and lem(4) ethernet drivers are now 
implemented via
         IFLIB.  If you have a custom kernel configuration that excludes 
         but you use igb(4), you need to re-add em(4) to your custom 

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