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From: Renato Golin (rengolin_at_[hidden])
Date: 2006-12-20 10:47:48


On 12/20/06, Harakiri <harakiri_23_at_[hidden]> wrote:
> I will study through the suggested paper, however
> i actually read a different paper which suggested
> using less messages, i would imagine that for arrays
> of numbers lets say 100 Millions - the network
> messages become the critical factor.

IMHO,

It depends completely on your network topology and technology (ie.
bandwidth and latency). It's very hard to predict a generic behaviour
other than: "more data is worse".

Ethernet is quite good at bandwidth but not at latency so a few big
chunks are better than lots of small chunks but it also depends how
the network is carrying your packages along the way.

The network is a critical factor only if it's running time is
comparable or greater than the processing time. Copying 1Mb between
nodes is critical for a nanosecond computation but not if it'll take
days.

cheers,
--renato

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