POV-Ray : Newsgroups : povray.text.scene-files : Filed() macro for CSV data file handling : Re: Filed() macro for CSV data file handling Server Time
6 Dec 2021 13:24:17 EST (-0500)
  Re: Filed() macro for CSV data file handling  
From: William F Pokorny
Date: 27 Oct 2021 07:02:54
Message: <617931de$1@news.povray.org>
On 10/26/21 9:57 AM, jr wrote:
> "jr" <cre### [at] gmailcom> wrote:
...
> 
> with 100k sphere centre and radius records for instance, POV-Ray needs around
> one second for the writing and the same for the read back.  Filed() comes in at
> around eight seconds write and ten seconds read.
> 

Hi,

I'm a little surprised at the magnitude of the slow down. Are you timing 
with a v3.8 beta or something else? I'm expecting the files are all on a 
ramdisk?

Thinking aloud...

If a povr branch, was it heavily optimized ahead of the build/make via 
configure script options?

Re: The povr branch is running with a C++11 string hash function for the 
symbol tables in the parser / vm over the traditional POV-Ray one. In my 
testing the C++11 one is only faster if the compile options are 
relatively aggressive(1,2).

In general, with the dictionary stuff being relatively new to v3.8, 
there is likely room to make the parser faster around that functionality.

I'd be willing to play a little with your 100K spheres case - if you 
want?

Bill P.

(1) - A reminder, the povr branch build system does NO optimization by 
default when the configure script is run.

(2) - The C++11 hashing of strings is much better, but it's more complex 
code and takes longer than POV-Ray's method. The old hashing tends to 
clump table entries around the leading ascii character value(s).


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