[postgis-devel] Another Data Point

[Mark Cave-Ayland]

Paul Ramsey wrote:

> Interesting! The Shark only samples for about 20 seconds, so I only
> got the first 10% or so of the run, and the biggest user in that time
> period memcpy'ing in LWGEOM_accum (postgis) and
> advance_transition_function (pgsql). So we are spending a non-trivial
> amount of time just accumulating the input...
> 
> P

Yeah, I think this came out of some of Regina's observations earlier 
when she was looking at changing the function; constantly accumulating 
onto the end of an array is slow since we repalloc() the memory and 
rebuild the entire type each time through...


ATB,

Mark.

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Mark Cave-Ayland
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