[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: single cable dual nic?



On 25 April 2011 13:19, Jim Green <student.northwestern@gmail.com> wrote:
> On 25 April 2011 09:32, Henrique de Moraes Holschuh <hmh@debian.org> wrote:
>> On Sun, 24 Apr 2011, Jim Green wrote:
>>> I have a asus p8p67 deluxe board and it has two nics and two ports, I
>>> am thinking of bonding them to one nic, but I only have one cable so
>>> will only use one port. Will this do much help to the
>>> throughput/speed? If I have two cables connecting to both ports I
>>> think it will definitely help, but here I only be using one cable/one
>>> port and two nics bonded to one virtual nic.
>>
>> Your board has Realtek 8111Es for NICs.  I won't sugar-coat it: that
>> stuff cannot be called good gigabit ethernet NICs in any way.  Its only
>> saving grace is that it is dirty cheap.
>>
>> Try to get jumbo frames working on your network, it should help you get
>> better throughput _if it works right_.  You just have to set the MTU to
>> the *same jumbo frame size* on *every host on your network* to enable
>> that.  But make sure your switch can handle jumbo frames first, and that
>> such support is enabled.
>>
>> Example jumbo MTU sizes: 9000, 7200, 4000.  Which one you can reliably
>> use depends on the least capable device in your network and their bugs.
>>
>> I would expect bonding to actually make things worse with r8169-based
>> NICs, but maybe it would distribute the interrupts better and give you
>> better performance at the cost of wasting even more CPU resources.  This
>> is only cost-effective if you happen to have a gigabit managed switch
>> capable of link bonding (LACP) already, or when directly connecting two
>> computers.
>>
>> Bonding with just one cable simply doesn't help performance.  Either the
>> devices notice the missing link and disable the offending ports (and you'll
>> be slightly worse off than you'd be without any bonding in the first place),
>> or you will have the packet loss from hell.
>>
>
> Looking at this, I think I am better off disabling the realtec nic and
> use intel® 82579 Gigabit LAN controller on the board instead.

Btw, will be using e1000e module for this nic.


Reply to: