Mental ray in 2012 - whhhhaaaaatt??

[Chris_TC]

I just ran some render tests in 2012, and the results have shocked me. I took a scene from 2011 and rendered it in both 2011 and 2012. I changed NO SETTINGS. Pre-processing time is identical in both versions and takes only a few seconds. However the buckets render WAY more slowly in 2012. What is going on? 2011 is around twice as fast on my system.

The scene uses a ton of ICE instances and very little "real" geometry. P.S.: I overlayed the results in Photoshop, and the final images are identical in both versions. But 2012 takes twice as long.

[Chris_TC]

OK, now I'm really confused. I just rendered a completely different scene: no ICE instances, just a lot of raw geomtry. 600 objects, 4 million triangles, lots of high-res textures, glossy reflections on just about everything, multiple area lights.
2012 took considerably longer to pre-process, but even taking this into account, the scene rendered in roughly half the time 2011 took. Once the buckets started rendering it was as if somebody had enabled TURBO mode compared to 2011.

Can somebody confirm that ICE instances and pre-processing are much slower while everything else is much faster? I'm very confused.

P.S.: None of my scenes used indirect illumination of any kind. Both used ambient occlusion though.

[Memag]

It's been discussed here:

Softimage 2012 Experiences

[origin]

I think memory footprint for ICE instances is much lower. One more test:

Scene to test (2011) http://dl.dropbox.com/u/8079325/instanc ... s_2012.rar

log from 2011:

Code: Select all

// INFO : SCEN 0.4  info : 7526 geometry leaf instances (26 scheduled, 0 cached, 7500 shared)
// INFO : SCEN 0.4  info : 1 light leaf instance
// INFO : SCEN 0.4  info : wallclock  0:00:00.07 for scene preprocessing
// INFO : SCEN 0.4  info : allocated 36 MB, max resident 634 MB
// INFO : RC   0.4  info : scene extent: (-4.40,-4.08,-10.57) : (4.40,3.29,4.40)
// INFO : RC   0.4  info : option: scanline          off
// INFO : RC   0.4  info : option: trace             on
// INFO : RC   0.4  info : option:   trace depth     reflection 5, refraction 5, sum 10
// INFO : RC   0.4  info : option:   acceleration    bsp2
// INFO : RC   0.4  info : option: shadow            segments
// INFO : RC   0.4  info : option:   shadow maps       (use) (recompute) 
// INFO : RC   0.4  info : option: lightmap          on
// INFO : RC   0.4  info : option: motion            off
// INFO : RC   0.4  info : option: luminance weights 0.212671 0.71516 0.072169
// INFO : RC   0.4  info : option: caustic           off
// INFO : RC   0.4  info : option: globillum         off
// INFO : RC   0.4  info : option: finalgather       off
// INFO : RC   0.4  info : option: samples           min -1, max 1
// INFO : RC   0.4  info : option:   contrast        0.2 0.2 0.2 0.2, all buffers
// INFO : RC   0.4  info : option: jitter            1
// INFO : RC   0.4  info : option: filter            triangle 2 2
// INFO : RC   0.4  info : option: render space      object
// INFO : RC   0.4  info : option: face              both
// INFO : RC   0.4  info : option: field             off
// INFO : RC   0.4  info : option: hair              on
// INFO : RC   0.4  info : option: task size         64
// INFO : RC   0.4  info : option: pixel preview     off
// INFO : RC   0.4  info : option: lens              on
// INFO : RC   0.4  info : option: volume            on
// INFO : RC   0.4  info : option: geometry          on
// INFO : RC   0.4  info : option: displace          on
// INFO : RC   0.4  info : option: premultiply       on
// INFO : RC   0.4  info : option: colorclip         rgb
// INFO : RC   0.4  info : option: output            on
// INFO : RC   0.4  info : option: merge             on
// INFO : RC   0.4  info : option: fb mem management cached
// INFO : RC   0.4  info : option: type     filter     name
// INFO : RC   0.4  info :         rgba_fp  yes        color
// INFO : RC   0.4  info : camera: focal length      35
// INFO : RC   0.4  info : camera: aperture          35.3887
// INFO : RC   0.4  info : camera: aspect            1.77778
// INFO : RC   0.4  info : camera: resolution        1280 720
// INFO : RC   0.4  info : camera: clip              0.1 32768
// INFO : RC   0.4  info : camera: frame             2 0.0833333 0
// INFO : RCI  0.4  info : using BSP2 for eye rays
// INFO : RCI  0.4  info : using BSP2 for secondary rays
// INFO : RCI  0.4  info : wallclock  0:00:00.00 for intersection prep.
// INFO : RCI  0.4  info : allocated 40 MB, max resident 634 MB
// INFO : RC   0.4  info : rendering statistics
// INFO : RC   0.4  info :   type                           number   per eye ray
// INFO : RC   0.4  info :   eye rays                       699481          1.00
// INFO : RC   0.4  info :   reflection rays               1065199          1.52
// INFO : RC   0.4  info :   shadow rays                  32968421         47.13
// INFO : RC   0.4  info : wallclock  0:00:57.24 for rendering
// INFO : RC   0.4  info : allocated 79 MB, max resident 634 MB
// INFO : GAPM 0.4  info : triangle count (including retessellation) :      425104
// INFO : PHEN 0.4  info : Reflection rays skipped by threshold: 223043

Log from 2012:

Code: Select all

# INFO : MEM  0.4  info : total memory: 12279 Mb 
# INFO : MEM  0.4  info : free memory : 8030 Mb 
# INFO : SCEN 0.4  info : 7526 geometry leaf instances (26 scheduled, 0 cached, 7500 shared)
# INFO : SCEN 0.4  info : 1 light leaf instance
# INFO : SCEN 0.4  info : wallclock  0:00:00.08 for scene preprocessing
# INFO : SCEN 0.4  info : allocated 36 MB, max resident 80 MB
# INFO : RC   0.4  info : scene extent: (-4.40,-4.08,-10.57) : (4.40,3.29,4.40)
# INFO : RC   0.4  info : option: scanline          off
# INFO : RC   0.4  info : option: trace             on
# INFO : RC   0.4  info : option:   trace depth     reflection 5, refraction 5, sum 10
# INFO : RC   0.4  info : option:   acceleration    bsp2
# INFO : RC   0.4  info : option: shadow            segments
# INFO : RC   0.4  info : option:   shadow maps       (use) (recompute) 
# INFO : RC   0.4  info : option: lightmap          on
# INFO : RC   0.4  info : option: motion            off
# INFO : RC   0.4  info : option: luminance weights 0.212671 0.71516 0.072169
# INFO : RC   0.4  info : option: caustic           off
# INFO : RC   0.4  info : option: globillum         off
# INFO : RC   0.4  info : option: finalgather       off
# INFO : RC   0.4  info : option: samples           min -1, max 1
# INFO : RC   0.4  info : option:   contrast        0.2 0.2 0.2 0.2, all buffers
# INFO : RC   0.4  info : option: jitter            1
# INFO : RC   0.4  info : option: filter            triangle 2 2
# INFO : RC   0.4  info : option: face              both
# INFO : RC   0.4  info : option: hair              on
# INFO : RC   0.4  info : option: task size         64
# INFO : RC   0.4  info : option: pixel preview     off
# INFO : RC   0.4  info : option: lens              on
# INFO : RC   0.4  info : option: volume            on
# INFO : RC   0.4  info : option: geometry          on
# INFO : RC   0.4  info : option: displace          on
# INFO : RC   0.4  info : option: premultiply       on
# INFO : RC   0.4  info : option: colorclip         rgb
# INFO : RC   0.4  info : option: output            on
# INFO : RC   0.4  info : option: merge             on
# INFO : RC   0.4  info : option: texture cache     local
# INFO : RC   0.4  info : option:   limit           dynamic
# INFO : RC   0.4  info : option: fb mem management cached
# INFO : RC   0.4  info : camera: type     filter     name
# INFO : RC   0.4  info :         rgba_fp  yes        Main
# INFO : RC   0.4  info : camera: focal length      35
# INFO : RC   0.4  info : camera: aperture          35.3887
# INFO : RC   0.4  info : camera: aspect            1.77778
# INFO : RC   0.4  info : camera: resolution        1280 720
# INFO : RC   0.4  info : camera: clip              0.1 32768
# INFO : RC   0.4  info : camera: frame             2 0.0833333 0
# INFO : RCI  0.8  info : using BSP2 for eye rays
# INFO : RCI  0.8  info : using BSP2 for secondary rays
# INFO : RCI  0.8  info : wallclock  0:00:00.01 for intersection prep.
# INFO : RCI  0.8  info : allocated 43 MB, max resident 80 MB
# INFO : RC   0.4  info : rendering statistics
# INFO : RC   0.4  info :   type                           number   per eye ray
# INFO : RC   0.4  info :   eye rays                       706139          1.00
# INFO : RC   0.4  info :   reflection rays               1079569          1.53
# INFO : RC   0.4  info :   shadow rays                  20116471         28.49
# INFO : RC   0.4  info : wallclock  0:00:38.60 for rendering
# INFO : RC   0.4  info : allocated 74 MB, max resident 104 MB
# INFO : GAPM 0.4  info : triangle count (including retessellation) :      425104
# INFO : IMG  0.4  info : total for cached textures and framebuffers:
# INFO : IMG  0.4  info :           7372800 pixel accesses
# INFO : IMG  0.4  info :              1566 pages loaded/saved, 0.0212402% image cache failures
# INFO : IMG  0.4  info : maximal texture cache size: 290 pages, 4.531 MBytes
# INFO : IMG  0.4  info : uncompressed cached texture I/O: 14.375 MB
# INFO : PHEN 0.4  info : Reflection rays skipped by threshold: 227028

Differences:
2012:
# INFO : RC 0.4 info : shadow rays 20116471 28.49
# INFO : RC 0.4 info : wallclock 0:00:38.60 for rendering
# INFO : RC 0.4 info : allocated 74 MB, max resident 104 MB

2011:
// INFO : RC 0.4 info : shadow rays 32968421 47.13
// INFO : RC 0.4 info : wallclock 0:00:57.24 for rendering
// INFO : RC 0.4 info : allocated 79 MB, max resident 634 MB

So 2012 20 sec faster...due to shadow rays being faster (portal light)

Now replacing portal light shader with standard soft light shader:

2012:
# INFO : RC 0.7 info : shadow rays 9621368 12.99
# INFO : RC 0.4 info : wallclock 0:00:24.48 for rendering

2011:
// INFO : RC 0.4 info : shadow rays 15469267 21.34
// INFO : RC 0.4 info : wallclock 0:00:34.05 for rendering