Re: [Closed REQ 5429]: Hardware!

["Mark Phillips" <mbp>]

> Systems that have been proposed to me include:
> 
> - Silicon Graphics Indy, R4400SC @ 175 MHz, 8-bit XL graphics, 1MB
>   secondary cache, 1 GB hard disk, 64 MB memory, 17" monitor.
>   (SPECint92 122.6, SPECfp92 115.5, AIM 118.4)
> 
> - Sun Sparc 20 model 61, running at 60 MHz, "Supercache", 8-bit
>   accelerated graphics, 20" monitor, 64 MB, 1.05 GB disk.
>   (SPECint92 93.0, SPECfp92 106.0, AIM 63.1)
> 
> - DEC Alpha 200 running at 166 or233 MHz with 8-bit graphics, 64 MB,
>   21" monitor, 1 GB hard disk. Cache?
>   (166 MHz SPECfp92 134.8, 233 MHz SPECfp92 183.9)

Geomview will run on any of these machines, more or less properly.
However the SGI version is the fasteest and most robust, because we
originally developed Geomview on an SGI, and because SGIs are
streamlined for 3D graphics.  If you plan to make significant use of
Geomview, then I would strongly recommend that you go with an SGI.
Although some other comparably priced machines may be faster for
computations, the difference isn't significant enough to outweigh the
great 3D graphics performance of an SGI.

For Surface Evolver and other computational programs, obviously you
want a fast CPU and lots of memory, and it's pretty easy to measure
these things.  Geomview's performance, however, depends more on the
graphics hardware (as well as the CPU).  You don't have to have XZ
graphics on an SGI; Geomview will run on any SGI.  But the graphics
option can significantly affect the speed.  

Ideally you should get the Indy above with XZ graphics, but if that
isn't within your budget, then you have to compromise.  What it boils
down to in your case is that you have to find an acceptable balance
between nice graphics and computational speed.

A lot depends on the level of complexity of the objects you anticipate
viewing.  If they will typically consist of just a few hundred
polygons (or mesh vertices), then graphics speed isn't so important.
It gets more imporant with larger objects.  Once you get up to several
thousand polygons or vertices, some of the slower graphics machines
become essentially unusable, because it each screen refresh can take
several seconds.  A word of warning, though: graphics speed is like
disk space --- whatever amount you decide is enough today, you'll need
10 times that much a year from now, :-).

I've included a table of Geomview speed tests below that we've put
together; The Indy you propose above isn't in the table, but
nevertheless you can get an idea of how various graphics options
affect Geomview's performance.  (If you have access to a machine like
the one you're considering buying, you can ftp the file
"priv/slevy/geomview-speedtests.tar.Z" from geom.umn.edu and run the
tests on that machine yourself.)

Notice that the table is sorted so that slow machines are at the top,
fast ones at the bottom.

One final note: 24-bit graphics displays look significantly better
than 8-bit ones.  8-bit displays look grainy and aren't able to show
as many colors (this can seriously affect shading in Geomview).
Depending on the level of complexity of the images you'll be looking
at, you might be perfectly happy with an 8-bit display --- many people
are.  But I mention this just because it's important to know that
there is a significant difference.

I hope this helps, and good luck!

Mark Phillips
Technical Staff Manager
Geometry Center


------------------------------------------------------------------------

# Tests: "polygon" : 1620 small flat-shaded LIGHTED polygons
# 	 "matrix"  : 30 vectors x 115 matrices
#	 "tmesh"   : flat-shaded LIGHTED tmesh sphere: 35 rows of 70 tri's
#			(Uses tmesh primitive on SGI; other platforms just
#			 draw 35x35 quadrilateral mesh)
# All tests in 200x200 window; all polygons are flat-shaded and LIGHTED.
# Times are milliseconds per test cycle.

	       polygon	matrix tmesh
Sun: X Geomview 1690	 1980  1440	bers (Sparc 1+ GX, X11R5 server)
NextStn Color	 675	 2700	415	quasifuchs (NextStation Color)
NextStn Turbo	 525	 2130	333	diophantus (NextStation Turbo B/W)
NextStn Trb Clr	 500	 2150	320	archimedes (NextStation Turbo Color)
NextCube NDmns	 720	 4500	400	schottky (NextCube w/NextDimension)
NextCube,ND,3.1	 890	 6050	490	schottky (NextCube w/ND, 3.1)
Gateway '486 PC  475	  620   387	kowalevsky (486 66MHz PC, Linux 0.99.14)
HP Gecko, NS3.2  430     1480   290	HP712/60, Nextstep 3.2; cc -g
HP Gecko, NS3.2  440     1325   287	HP712/60, Nextstep 3.2; cc -O
Gateway '486 PC	 425	 1600	250	kowalevsky (486 66MHz PC, NS 3.1)
Gateway '486 PC	 405	  512   325	kowalevsky (Linux 0.99.14, COPTS=-O)
Pers Iris 25G	 400	  900	400	bolyai (Pers Iris 4D/25G)
HP Gecko, HP-UX  311      430   258     32 MB HP 712/60, Geomview 1.4.2
HP Gecko, HP-UX  285	  290	233	ditto, With Geomview 1.5
Indy 8bit PCach	 275	  500	260	48MB Indy,8bit,primary cache only
Sparc-10, X11R5	 257	  280	205	Sparcstation 10, X11R5 server
ALR Pentium PC	 230	  912   145	60MHz Pentium, NS 3.1, ALR Evolution V
Sparc-10, X11R5	 220	  220   180	Sparc 10, Geomview 1.5
RS/6000-370	 194	  285   149
R3000 Basic	 175	  310	130	ricci(R3K Indigo/basic graphics)
Pers Iris 30G	 240	  163	228	euclid  (Pers Iris 4D/30G)
Pers Iris 20GT	 116	  360	119	nielsen (Pers Iris 4D/20GT)
R3000 XS24	 137	   99	 84	weyl    (R3000 Indigo XS24Z)
R3000 XS24	 185	   90	110	weyl    (R3000 Indigo XS24Z)
Indy R4000SC	  83	  166    71	Indy R4000SC, 24-bit graphics
Indigo-2 XZ	  76	   59	 45	abel    (Indigo-2 XZ)
R4000 XZ	  69	   60	 42	banach  (R4000 Indigo XZ)
R4000 Elan	  43	   89		lebesgue.msri.org  (R4000 Elan)
R4400 Indy	  42	   95	 40	R4400 Indy SC, 24-bit graphics
Indigo-2 Extreme  24	   52	 15	nonabel (Indigo-2 Extreme)
Crimson VGX	  25	   61	 12	gauss   (Crimson VGX)

Hardware notes:
  "Gateway '486 PC" - Geometry Center
    256k cache.  What graphics board? ATI Graphics Ultra Pro (VLB)

  "ALR Pentium PC" - Andreas Windemuth, windemut at cumbnd.bioc.columbia.edu:
    2Mb ATI Ultra Pro VLB board, running the updated driver from NeXTanswers
    at 1120x832/RGB555:16. The ALR has a 64 bit data path and 256k of cache.