Re: [boost] [string] proposal

Subject: Re: [boost] [string] proposal
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2011-01-28 00:30:11

AMDG

On 1/27/2011 2:52 AM, Dean Michael Berris wrote:
> 5. Because of the contiguous requirement, using it for any "text"
> that's larger than a memory page's worth of data will kill your cache
> coherency -- and then when you modify parts of it then you can thank
> your virtual memory manager when the modifications are done. Then you
> see that you would have to implement your own segmented data structure
> to act as a string and then you realize you're better off not using
> std::string for situations where the amount of data you're going to
> deal with is potentially larger than cache line.
>

I beg your pardon, but this makes no sense to me.
Would you mind explaining exactly what kind of
usage makes the hardware unhappy and why?  I'm
not even sure what this has to do with cache coherency
(http://en.wikipedia.org/wiki/Cache_coherence).

In Christ,
Steven Watanabe