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From: Ted Dunning <ted.dunning@gmail.com>
Date: Fri, 8 Jul 2011 08:06:41 -0700
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Subject: Re: [math] Iterative linear solvers (MATH-581) again
To: Commons Developers List <dev@commons.apache.org>
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As your measurements indicate, the allocation of large objects is rarely a
speed issue.  It can be a memory fragmentation issue, but a full GC will fi=
x
that as well.

People who are stressed about allocation of result vectors such as what you
are doing are mostly worried about the wrong thing.

2011/7/8 S=C3=A9bastien Brisard <sebastien.brisard@m4x.org>

> The thing is the first option is not frequently met in Commons-Math.
> I've started to work with this option for iterative linear solvers,
> but I do not like the inconsistent feel it has with the rest of CM.
> Also, very crude monitoring on rather large linear systems (800,000 x
> 800,000)  shows that memory allocations are not even measurable... As
> I said, I read that a long time ago, and someone already mentioned on
> this forum that GC is getting pretty good those days... So is it
> really worth worrying about memory allocation?
>

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