Re: [boost] Re: boost::pool speed tests

From: Beman Dawes (bdawes_at_[hidden])
Date: 2003-05-08 09:04:21

At 07:28 PM 5/7/2003, Darren Cook wrote:

 >Well it was a real-world example and I only applied it to one of the
 >classes. 2-3% speed boost for only three extra lines of code (header
 >include, new, delete) is worth having.

A 2-3% timing difference probably isn't reliably repeatable in real code.

How code and data happens to land in hardware caches can easily swamp out 
such a small difference. The version-to-version or step-to-step differences 
in CPU's, memory, compilers, or operating systems can cause that much 
difference in a given program. Differences need to get up into the 20-30% 
range before they are likely to be reliably repeatable across different 
systems.

At least that's been my experience.

--Beman