Boost logo

Boost :

Subject: Re: [boost] [xpressive] Performance Tuning?
From: David Abrahams (dave_at_[hidden])
Date: 2009-07-28 15:49:42

on Tue Jul 28 2009, Edward Grace <> wrote:

> This?
> There's some interesting trickery in there by the looks of things for eliminating the
> optimiser nastiness - that's not something I've thought about much I'll take a look.
> In the comments,
> 42 // operation to at least update the L1 cache. *** Note: This
> 43 // concern is specific to the particular application at which
> 44 // we're targeting the test. ***
> that seems quite important but a little opaque out of context.

It means the application we were going to use this technique on was
going to update a long series of accumulators, which will certainly not
fit in a few registers. We wanted to force the test to reflect that

> One thing I take exception to is the (effective) use of the mean as a
> measurement of central tendency


> - perhaps their trickery has eliminated the heavy tail.

Why would one assume there is a heavy tail in the first place?

Dave Abrahams
BoostPro Computing

Boost list run by bdawes at, gregod at, cpdaniel at, john at