I'm wondering if it's expected that Houdini 16 is much slower than 15.5 for GL performance.

Time to write OpenGL JPGs for attached very basic scene with no animation and 600,000 polygons:

15.5.717: 15.8 seconds
16 release: 41 seconds

That's clearly reflected in the viewport performance. I noticed the default shader is slightly different (phong vs lambert/flat) so it's possible this is expected.

note that the attached scenes use out node pre- post-scripts that do the benchmarking for you. I'll try on Windows now since I'm testing on MacBook Pro 2016 AMD 460 in 10.12.3 now.

same on Windows 10 with GTX 1070: 13 seconds (15.5) vs 30.1 seconds (16)

Quite a few things have been optimized in the viewport while the H16 release was being prepped, and this happens to be one of them. The next daily build has H16 much more competitive:

H15.5: 13.6s
H16.0.528: 14.0s

Note that H16 uses cusped normals by default, which is nicer (boxes look like boxes, with hard edges) but incurs a slight performance penalty as vertex normals are not natively supported by OpenGL and require an extra shader stage.

OK - thanks. Great release.

just ran test again on new 16.0.529 build and confirmed it's resolved. 16seconds vs 42seconds on release build. Thanks.