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Performance of GEGL

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Performance of GEGL Lavergne Thomas 09 Oct 18:22
Performance of GEGL Øyvind Kolås 09 Oct 20:48
Lavergne Thomas
2007-10-09 18:22:44 UTC (about 17 years ago)

Performance of GEGL

Hi,

I've just installed GEGL and BABL and started to do some test. For example the following code :

#include gint main(gint argc, gchar **argv) { GeglNode *gegl, *load, *size, *outp;

gegl_init(&argc, &argv); gegl = gegl_node_new();
load = gegl_node_new_child(gegl, "operation", "load", "path", "data/test.jpg", NULL); size = gegl_node_new_child(gegl, "operation", "scale", "x", 2.0, "y", 2.0, NULL); outp = gegl_node_new_child(gegl, "operation", "png-save", "path", "data/ouput.png", NULL);

gegl_node_link_many(load, size, outp, NULL); gegl_node_process(outp);

g_object_unref(gegl); gegl_exit();

return 0;
}

This code just load an image (620x450) scale it by 2 in each dimension and save it to an output jpeg file. So there is only simple operation on small image but it take more than 30sec at 100% cpu on my Pentium4 3.4GHz !!!

So is it me who had done something wrong ar is GEGL and BABL so slow ?

For simplicity I've used the last released version of both and not SVN version, but I don't think it will be so different. I suppose the error come from elsewhere.
Both library are compiled with dry run of ./configure, make and make install. The example program is compiled by :

cc -O3 -W -Wall `pkg-config --libs --cflags gegl` test.c -o test

and the output : thomas:~/test$ time ./test
buffer-leaks: 3

real 32.007 user 31.366
sys 0.612
pcpu 99.90

So does any of you have an idea about what can cause this slow down ?

Thanks

Tom

Øyvind Kolås
2007-10-09 20:48:05 UTC (about 17 years ago)

Performance of GEGL

On 10/9/07, Lavergne Thomas wrote:

Hi,

I've just installed GEGL and BABL and started to do some test. For example the following code :

So does any of you have an idea about what can cause this slow down ?

GEGL is still going through architectual level internal refactoring even though the public API
haven't changed much lately.

The slow down can come from quite a few different places, and it might even be slower if you try the SVN version since it is in, and has been in for a while, a intermediate state where a new caching framework is being integrated. If babl's extensions aren't being automatically
picked up the interpolation that happens during affine transformations will be slower as well.

To figure out where time is spent set the environment variable GEGL_DEBUG_TIME to some value and study the output, the results of which is meaningless for the last released version since the affine (scaling) operations has been significantly changed; as well as for the SVN version since there are some semi-known issues with the still fresh caching code.

/Øyvind K.