Re: Warm-cache prefetching

Kenneth Marshall wrote:
> The main benefit of pre-fetching optimization is to allow just-
> in-time data delivery to the processor. There are numerous papers
> illustrating the dramatic increase in data throughput by using
> datastructures designed to take advantage of prefetching. Factors
> of 3-7 can be realized and this can greatly increase database
> performance. The first step needed to take advantage of the ability
> of pre-fetching to reduce memory latency is to design the index
> page layout with an internal blocking of the cache-line size.
> Then issue pre-fetch instructions for the memory you are going
> to need to process the index page far enough in advance to allow
> it to be in a cache-line by the time it is needed. 

I can see that being useful for a single-user application that doesn't
have locking or I/O bottlenecks, and doesn't have a multi-stage design
like a database.  Do we do enough of such processing that we will _see_
an improvement, or will our code become more complex and it will be
harder to make algorithmic optimizations to our code?

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