Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!rpi!batcomputer!thompson
From: thompson@batcomputer.tn.cornell.edu (Steve Thompson)
Newsgroups: comp.sys.dec
Subject: Re: Comments on relative graphics performance: VAX3100 vs. DEC3100
Message-ID: <9383@batcomputer.tn.cornell.edu>
Date: 3 Dec 89 14:52:17 GMT
References: <12528@watcgl.waterloo.edu>
Reply-To: thompson@tcgould.tn.cornell.edu (Steve Thompson)
Distribution: comp
Organization: Cornell Theory Center, Cornell University, Ithaca NY
Lines: 25

In article <12528@watcgl.waterloo.edu> idallen@watcgl.waterloo.edu writes:
>From: "Ian! D. Allen [CGL]" <idallen>
>
>DEC showed off a 8Mb VAXstation 3100 and a 16Mb DECstation 3100.  The VAX
>was running VMS; the RISC was running Ultrix.  Both ran X windows.
>
>What surprised me was the lack of speed of the RISC machine when dealing with
>the graphics display.  The VAX (at one-fifth the CPU speed) with its hardware
>assist moved pixels around the screen about twice as fast as the RISC.
>(I was using the cut/drag feature of dxpaint and the xplaid demo as tests.)
>
[etc]

We have both VS3100's and DS3100's. The greatest speed difference that I
have seen between the two machines on floating intensive code is a factor
of 3.3. My biggest application runs 20% faster on the VS3100 than on
the DS3100! Put the two machines side by side and log in on both at the
same time; which comes up with the window first? The VS3100. BTW, the
VS3100 has 8MB, DECwindows, VMS V5.2. The DS3100 has 12MB, UWS 2.0. Both
are diskless machines; the DS3100 served by another DS3100, the VS3100
from a VAX 8250. Before we went to 12MB on the DS3100, it had 8MB, and
one f77 program took 5.5 hours to compile; now it takes 3.5 minutes.
On the VS3100, the same program compiles in 30 seconds.

Steve