Graphics Benchmarking

[Jim Barton]

I'm posting this article in reply to an early article asking how we benchmark
our graphics hardware.  Direct responses and queries can be sent to
kurt at sgi rather than myself.

-- jmb

===============================================================================

    This note is a response to Barry Fowler's message of 15 February 1989.
    Barry referenced our '88 SIGGRAPH paper (High Performance Polygon
    Rendering) and asked several questions concerning it and the system
    that it describes.  His questions (paraphrased by me) and our responses
    are:

    1.	What system do the benchmark figures in the paper correspond to?

	They are for the dual-processor GTX (4D-120) product.  However,
	only one of the CPU's is used during the benchmark (the other
	is available for general purpose computing).

    2.	Were the benchmark figures computed, or were they measured on
	actual equipment?

	We ran the benchmarks on the prototype GTX hardware that was
	available at the time.  I reran the benchmarks on current
	equipment, and have included the new figures below.

    3.	Will SGI distribute the binaries of the benchmark programs?
	Perhaps even source code?

	We are happy to distribute both binary and source to customers
	through our sales/service organization.
    
    The performance figures claimed in the paper (and the current
    figures) are:

            - 101,000 quadrilaterals per second.  100 pixel,
              arbitrarily rotate, lighted, Z-buffered.

	      (102000, up 1 percent)

            - 137,000 triangles per second.  50 pixel, arbitrary
	      strip direction, lighted, Z-buffered.

	      (135000, down 1 percent)

            - 394,000 lines per second.  10 pixel, arbitrarily
	      directed, depthcued, Z-buffered.

	      (334000, down 15 percent)

            - 210,000 antialiased lines per second.  10 pixel,
	      arbitrarily directed, Z-buffered.

	      (175000, down 17 percent)

            - 8.3 millisecond full-screen clear.  Both color and
	      Z-buffer banks cleared.

	      (8.2, up 1 percent) 

    Current polygon and area fill benchmark results are all within one
    precent of the figures claimed in the paper.  Line drawing rates,
    however, are down roughly 15 percent from the claimed values.
    This performance loss is the result of a bug fix correcting the
    hardware interaction of polygon patterning with line drawing.
    We expect that future microcode releases will restore the line
    drawing performance to previously measured values.

-- kurt