Simple X windows benchmark

[Richard Foulk]

In article <3858 at tuminfo1.lan.informatik.tu-muenchen.dbp.de> roell at lan.informatik.tu-muenchen.dbp.de (Thomas Roell) writes:
>First some test results:
>
>	UNIX:		ISC 2.0.2
>	X server:	X386 (X11R4) internal test version
>	Video card:	VGA GENOA 5400
>	CPU:		33 MHz, 32k cache, 8MB (PizzaMan's Special)
>	30387:		no
>
>a)	Resolution:	864x606x2
>	Time:		0:59
>
>b)	Resolution:	800x600x256
>	Time:		3:40
>

Thanks for the data.

> [...]
>Let's do now a interpretation of the test: (Since I didn't use prof(1) for this
>test all numbers below are estimates) About 80% of the test is spent in the
>scroll, 10% in a fill and 10% in a glyph painting routine. Was this intended ??

Yes.

> [...]
>But no critic without saying what could be done better. As I posted some days
>ago you should use a special benchmarking utility. X11PERF is such an utility.
>It can be found under the X11R4-tape (contrib/demos/x11perf). The port to X11R3
>should be simple. Running all test will take some hours (4 to 5). But then you
>will have results that are saying some more than the above test does.

That tests things that I'm not concerned with.  But more importantly
it's not a test that you're likely to get many people to run -- it's
just too much trouble.  (I've only gotten 18 responses to my simple
benchmark so far.  Thanks very much to those who've taken the time to
run it and send their results!)

>
>Gary Lewin told us his VGA did the test in 13.31s. That means his VGA has a
>throughput of 80x8x23x13x(1000-24)x2/13.31s = 26.76 MBytes/sec. (I did not
>use the fact that the test uses only 80% in scrolling, so the more realistic
>throughput has to be around 33 MBytes/sec) If his Graphics board allows 16bit
>(ISA bus) access, his CPU MUST have an i/o speed of 13.5 MHz (assuming
>the VGA allows zero wait state access, and the CPU can access video memory
>parallel to the VGA's display unit; if you'll take 33 MB/sec it will be 17 MHz
>i/o speed). This is faster than every board (CPU & VGA combination) I ever
>heard of!! Please, Gary post realistic results, or tell us how your VGA works
>(EISA bus, VRAM's, graphics processor and so on), and where to get it. 

A growing number of cards don't require the cpu to do the scrolling,
they have an on-board processor to do the work.  Cpu and bus speeds
should be mostly irrelevant for scrolling.

I'm interested in scrolling because it's the only performance aspect
that comes close to being unacceptable on some systems I've tried.
Yes, I use jump-scrolling, but too often it doesn't work very well.
Some programs send text just slow enough to circumvent jump-scrolling.

I'll post the benchmark summary in a day or two.  I was hoping to get
more responses, especially from people with faster cards, 8514's and
such, but I've only received a couple.

Someone complained that too much time is spent within awk, and that
this invalidated the benchmark results.  In my tests, on a machine with
no fpu, when I redirect the test to /dev/null it takes less than one
second to run.  This is insignificant compared to the average benchmark
run time of over a minute.  (When I was devising the benchmark, I
considered sending awk's output to a file and then timing a "cat" of
the file, but I decided it wasn't necessary.)


If you haven't run the benchmark yet please do so and send me the
results.  It's short and fairly simple, just in case you missed it,
here it is again:

To run the benchmark start up an xterm like this:

	xterm -geometry 80x24 -fn 8x13 +j &

then put the following awk script in a file called x-test:
-----------------------------cut here----------------------------
BEGIN {
	for (i = 0; i < 1000; i++) {
		printf("xxxxxxxxxxxxx %d\n", i);
	}
	exit;
}
-----------------------------cut here----------------------------
Run it, from the above mentioned xterm, like this:

	time awk -f x-test

and report the real time results.


Thanks very much.