Path: utzoo!attcan!utgpu!watserv1!watcgl!idallen From: idallen@watcgl.waterloo.edu Newsgroups: comp.sys.dec Subject: Comments on relative graphics performance: VAX3100 vs. DEC3100 Message-ID: <12528@watcgl.waterloo.edu> Date: 3 Dec 89 01:42:59 GMT Sender: idallen@watcgl.waterloo.edu Reply-To: idallen@watcgl.waterloo.edu Distribution: comp Lines: 23 From: "Ian! D. Allen [CGL]" 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.) As far as raw CPU power goes, any improvement in CPU on small applications seems hidden in the usual slowness of the disks. Starting up applications didn't seem to take any less time, though I didn't play much to get a better feel for this. I expect if you were an engineer running computation-intensive programs, this machine would seem really fast. Being a programmer, running compiles and program loads took about the same time as on our VAX8600. In fact, compiling the plaid.c X demo took twice as long on the RISC as on the 8600. So I guess I won't expect much RISC improvement for program development. I read in this group comments to the effect that the graphics hardware assist in the VAX machines would slow the RISC machine down. Well, if that's true, it certainly isn't evident in the two applications I ran.