anv: Lower gfxbench gl_driver2 performance under zink compared to iris
The gfxbench "gl_driver2" benchmark mostly consists of a loop doing glUniform3f()
and glDrawElements(GL_TRIANGLES)
(occasional other statechanges, but that's generally the thing). For radv and turnip, zink gets within about 5% of the native GL driver, but with anv on my CFL system the fps drops from 296 to 120 when I use zink instead of iris.
The GPU seems mostly busy -- 680mhz at 88% occupied according to intel_gpu_top
, compared to 93% at 750mhz for iris. CPU is pretty busy too, with some highlights being 14% in anv_CmdPushDescriptorSetWithTemplateKHR
(split between set_write_template
and push_descriptor_set
), 16% in cmd_buffer_flush_push_constants
, 7% in flush_descriptor_sets
We're interested in the results of this benchmark for Chrome OS because we expect that "small uniform update and draw a quad" looks like a lot of 2D workloads that we might be putting through zink+anv.