comp.os.linux.networking

Hello,

On Tue, 4 Mar 2008 13:14:06 -0800 (PST)
Greg.A.Fischer@gmail.com wrote:

[...]
> In an attempt
> to improve performance at a modest cost, we implemented NIC (channel)
> bonding.
>
> The results that I'm seeing, so far, aren't all that impressive. We
> bought a round of dual-port GigE NICs, so we're bonding 3 NICs per
> box. We have an 802.3ad-compliant switch (Linksys SLM2024), so we're
> running bonding mode=4, but we've tried several of the others, to
> little avail. The basic benchmarks we're running (subounce v.1.0) are
> only showing sporadic ~10% improvements in bandwidth and latency.
> Performance of our primary code of interest has only improved by a
> factor of 5%-20%, which is significantly less than I was expecting.

I never have experienced any throughput-gain by channel bonding on
Gigabit Ethernet (in contrast to Fast Ethernet).

If you need bonding for MPI applications only, then I would suggest to
use Open MPI [1]. This MPI implementation benefits from multiple NICs
without depending on the Linux bonding kernel module. For large
messages you should get an almost ideal speedup but the latency will
not decrease (no or little speedup for short messages).


Heiko


[1] http://www.open-mpi.org

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-- Cluster Computing @ http://www.clustercomputing.de
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