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Re: ::scr Touchy Feely?



On Thursday 24 October 2002 10:16, Andy Wardley wrote:

> For me at least, it has helped to formalise some concepts in my head,
> some of which I had seen or used before, but many of which I didn't have
> names for.  Now I find I can build high-level systems in my head by
> connecting these words together without the baggage of loading the actual
> algorithms and all their inherent noise into my limited brain space.

Yep; I've found the same thing with set theory (and the descendants - 
relations, categories, etc) when conceptualising data structures.

A queue is a queue, be it in memory as a linked list, or an SQL table that 
things get insterted into and we have a query that select-for-updates one row 
and deletes it. I can split a queuing system into two problems:

1) The code that puts things into the queue, and that processes stuff from 
the queue

2) The implementation of the queue

The two don't need to take each other into account. So they can change 
independently. I can write a really good in-memory queue implementation and 
share it around, and I can make my code switch between using a shared SQL 
queue and having an in-memory queue in each process with a system that 
randomly distributes new work to an idle node while figuring out which is 
faster.

ABS

-- 
A city is like a large, complex, rabbit
 - ARP