290.* drivers and OpenGL atomic counters

jeltz88 · 11-23-11, 03:17 AM

Hi,
I've been working with ARB_shader_atomic_counters in OpenGL 4.2.
I've notices a huge performance increase in atomic counters when changing from the 285.03 (beta) driver to 290.(06/10).
My assumption/speculation is previous GL4.2-capable drivers implemented atomic counters similarly to imageAtomicAdd from ARB_shader_image_load_store and atomicAdd from NV_shader_buffer_load and that the more recent drivers switched to using some form of dedicated hardware atomic counters.

Has anyone else noticed this change in atomic counter performance? If so, I'm interested to know why they were slow in the earlier drivers.

To test performance I'm simply incrementing a counter in the fragment shader.

Thanks in advance.

11-23-11, 03:17 AM	#1
jeltz88 Registered User Join Date: Nov 2011 Posts: 1	*290. drivers and OpenGL atomic counters** Hi, I've been working with ARB_shader_atomic_counters in OpenGL 4.2. I've notices a huge performance increase in atomic counters when changing from the 285.03 (beta) driver to 290.(06/10). My assumption/speculation is previous GL4.2-capable drivers implemented atomic counters similarly to imageAtomicAdd from ARB_shader_image_load_store and atomicAdd from NV_shader_buffer_load and that the more recent drivers switched to using some form of dedicated hardware atomic counters. Has anyone else noticed this change in atomic counter performance? If so, I'm interested to know why they were slow in the earlier drivers. To test performance I'm simply incrementing a counter in the fragment shader. Thanks in advance.