@ Alexey Suslikov <alexey.susli...@gmail.com> wrote (2011-06-01 21:04+0200):
> Why do they need such a trick instead of simply storing tags in a
> associative array, where key is a pointer and value is a set of tags
> (or any other arbitrary data)? Lookup against properly aligned array
> is relatively fast. Am I missing something?
May i answer this. One reason is of course space consumption.
If you have 10000 objects you need 10000 hash nodes and i don't
know how many indices the array shall have in this situation.
And also, following a pointer chain is poison for CPU cache
housekeeping. I.e. in that meaningless example
// _area->owner->cbin_table[u.cbin->cbin_index] = u.cbin;
you have to wait multiple times for memory to become available.
And this is *really* expensive!
--
Ciao, Steffen
sdaoden(*)(gmail.com)
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