From: Jay Vosburgh <fubar@us...> - 2005-03-19 07:44:04
Kumar Vaibhav <kvaibhav@...> wrote:
>I am trying for bonding in the Linux I am using Fedora 2 on 64 bit to
>team the two NICs togetther in for Link aggregation. And checking the
>bandwidth with Netpipe. I tried with mode=4 but the bandwidth
>available remains equal to that is available with a single port.
>Can you tell me what the problem is. I have a #com 4924 switch in
>that i have made 2 link aggregation of two ports each. and on both
>sides I have the simmilar machine with same bonding parameter.
>Can you help to figure me out the problem.
The 802.3ad standard requires that single "conversations" (TCP
connections) not stripe across multiple physical devices. If your
netpipe test is testing the throughput available to one TCP connection,
then this is the expected (indeed, for 802.3ad, the required) behavior.
The bonding 802.3ad implementation operates at a host level granularity,
therefore, all traffic to a particular peer on the local network (which
may be a gateway) will use the same interface of the bond.
This is the same behavior you will see for all bonding load
balance modes except for balance-rr, which distributes traffic
indiscriminately across all interfaces of the bond. That might get you
more throughput, and it might not; see the links in the last paragraph.
This behavior is, to some extent, an artifact of a limited test
environment (unless your real workload is just transferring data from
host A to host B). With multiple hosts on the network, the modes will
distribute traffic across the interfaces at a host granularity (i.e.,
specific hosts will generally use a particular interface), and the total
throughput will be higher than one interface's worth of throughput,
although no single host will (generally) see more than one interface's
There is more discussion about this in the current bonding
documentation (available on the bonding sourceforge site,
http://sourceforge.net/projects/bonding) and in the mailing list
archives (look for the subject "trunking performance").
-Jay Vosburgh, IBM Linux Technology Center, fubar@...
Get latest updates about Open Source Projects, Conferences and News.