nic performance: bce vs em

[Vladislav Prodan]

 --- Original message ---
 From: "Cristiano Deana" <cristiano.deana at gmail.com>
 Date: 16 July 2014, 18:32:44
  


> Hi all,
> 
> I'm gonna setup a Dell 1955 to use as router. Dual xeon dual core,
> with these network cards:
> 
> # pciconf -lv | grep -B2 network
> vendor = 'Broadcom Corporation'
> device = 'NetXtreme II BCM5708S Gigabit Ethernet'
> class = network
> --
> vendor = 'Intel Corporation'
> device = '82546GB Gigabit Ethernet Controller'
> class = network
> --
> vendor = 'Intel Corporation'
> device = '82546GB Gigabit Ethernet Controller'
> class = network
> --
> vendor = 'Broadcom Corporation'
> device = 'NetXtreme II BCM5708S Gigabit Ethernet'
> class = network
> 
> Now I have a similar machine, with only one CPU and using vlan based interfaces.
> A week ago I started collect flow data from interfaces with ng_flow
> and I have a high CPU usage:
> CPU 0: 0.0% user, 0.0% nice, 0.0% system, 21.7% interrupt, 78.3% idle
> CPU 1: 0.0% user, 0.0% nice, 1.6% system, 23.6% interrupt, 74.8% idle
> This is right now, with low traffic, so I'm gonna upgrade with new system
> 

Try to do these steps:

1) Go to the site DELL and see update firmware for embedded NICs.

2) Get a output sysctl kern.eventtimer.choice, and if there is LAPIC, try to change eventtimer

3) Disable options RXCSUM, TXCSUM, TSO4 from network cards Broadcom:

ifconfig bce0 -rxcsum -txcsum -tso ....
ifconfig bce1 -rxcsum -txcsum -tso ....

--
 Vladislav V. Prodan
 System & Network Administrator
 support.od.ua