Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site cmu-cs-wb1.ARPA Path: utzoo!linus!philabs!cmcl2!seismo!rochester!cmu-cs-pt!cmu-cs-wb1!avie From: a...@cmu-cs-wb1.ARPA (Avadis Tevanian) Newsgroups: net.unix-wizards Subject: Experience with MicroVAX II Message-ID: <222@cmu-cs-wb1.ARPA> Date: Wed, 15-May-85 23:51:22 EDT Article-I.D.: cmu-cs-w.222 Posted: Wed May 15 23:51:22 1985 Date-Received: Fri, 17-May-85 03:05:47 EDT Organization: Carnegie-Mellon University, CS/RI Lines: 78 As everyone now knows, DEC has officially announced the MicroVAX II. There have already been a couple of articles about this new machine, but far fewer than I had expected to see. So, here we go: I have been fortunate enough to field test a MicroVAX II (serial # PROTO 112!). I have been using my machine now for 2 1/2 months and have been running Ultrix-32m 1.1. My configuration: MicroVAX II CPU with Floating Point Chip. 5 Megabytes main memory. DZ (4 serial lines) 2 Floppies. 2 RD52 hard disks (~30 Meg each) (not the newer RD53's). DEQNA (10MB ethernet). TK-50 tape streamer. QVSS (bitmap display) (just installed yesterday!) (let's see, what else could I want?) 2 1/2 months ago a couple of us were told that a MicroVAX II was set up in our machine room. We couldn't find anyone who knew exactly were it was at the time, so went in search of it. We walked through three of our machine rooms, and finally found it hiding under a table. At this time, the machine only had a Decwriter attached to it, with about 5 sheets of paper in it. What had scrolled out was the results of diagnostics, which claimed that the machine had 5.0 Meg. Well, we didn't believe it, figuring that DEC diagnostics were screwed. So, we then proceeded to look at the box of floppies we had. We found one labelled "Boot 1 of 3" and another labelled "Boot 2 of 3" and inserted them into the floppy drives, typed "B" and watched Ultrix boot (we were then convinced the machine really had 5 Meg). It started asking us to insert more disks, we did. About 1/2 hour later, we were running multiuser Ultrix. Enough of this anecdote, time for some hard facts: Speed: The WORST CASE I have seen is 75% of a 780. Usually runs about 80-90% of a 780. Programs that make good register usage get 100% of 780. More importantly, it "feels" like a 780 (with only 1 user!). Floating point: OK, lots of machines can get close to 780 perfomance, but what about floating point? I thought for sure that this would be the place were the 780 would outperform the MicrooVAX... WRONG! The floating point chip is just as fast as a 780 with a FPA (actually, add/subtract are a little slower on MicroVAX, but not much). My instruction timings showed differences of 20% or less in floating point speeds (the MicroVAX actually seems to do floating divide faster than the 780). Compatibility: I copied emacs and scribe off one of our 4.2 780's and ran them without even recompiling them. There are a few problems though (like with CLU), so it is recommended that you recompile on the MicroVAX, but it is generally unnecessary. Bitmap display: I've only had a day to work with it, and I have only software than I have written. The display isn't overly impressive, but it does work. The main problem is that the display hangs off the Q-Bus... this seems to slow it down. For example, I can do graphics on the II about twice as fast as on a MicroVAX I, but for most other types of computation, the II is 3 to 5 time the speed of the I. Summary: The MicroVAX II is (in MY OPINION) clearly superior to other workstations I seen (SUN is going to take a BIG hit). Of course, I still haven't seen any 68020 based machines yet, but I doubt they will perform as well as the MicroVAX II. With the MicroVAX II you get everything on two chips (memory management is on the processor chip also), you get 785/780/750... compatibility (how many people couldn't run GNU emacs on the 68K box when it was first released, and how often to you run into problems with byte order because you want your program to run on both VAX and 68K?). Again, these are MY OPINIONS after using the machine for 2 1/2 months. I'm sure some people will agree, others will not. HIGHLY RECOMMENDED! Avie Tevanian Carnegie-Mellon University Department of Computer Science PS: The only gripes I have with DEC about the MicroVAX pertain to the announcement film: my advisor is "Rick" on Rich (pronounced incorrectly on film), and they cut all the film they took of me.