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- Subject: Re: [eigen] FLENS C++ expression template Library has excellent documentation
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Sat, 18 Apr 2009 12:48:18 -0400
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2009/4/18 Rohit Garg <rpg.314@xxxxxxxxx>:
>> There are different use cases.
>> - many products of many small matrices
>> - one product of two large matrices
>
> This kind of question needs thought. You see, I was pretty
> disappointed at the rather poor performance of eigen in the Pentium D
> benchmarks.
This can be explained by the use of GCC 4.3 in this benchmark which is
less good than GCC 4.2 and 4.4 for Eigen.
> I am thinking that that is due to there being machine
> dependent constants in the eigen which need to be tuned for each
> machine.
There is basically one constant to tune, the cache size.
Benoit