Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 UW 5/3/83; site uw-beaver Path: utzoo!watmath!clyde!burl!ulysses!mhuxj!houxm!hogpc!houti!ariel!vax135! cornell!uw-beaver!info-mac From: info-...@uw-beaver.UUCP Newsgroups: fa.info-mac Subject: experience at Rutgers with large intro courses Message-ID: <2195@uw-beaver> Date: Mon, 12-Nov-84 03:46:01 EST Article-I.D.: uw-beave.2195 Posted: Mon Nov 12 03:46:01 1984 Date-Received: Tue, 13-Nov-84 19:19:51 EST Sender: yenbut@uw-beave Organization: U of Washington Computer Science Lines: 205 From: Charles Hedrick <HEDR...@RUTGERS.ARPA> This message is an attempt to summarize our experience this fall. We are using Macs and Lisas for our first three computer science courses. These include an intro programming course, a second semester of programming (emphasizing data structures), and a course in assembly language and machine architecture (emphasizing the latter - we don't consider assembly language per se to be worth all that much). We have around 60 Macs, used for the first two courses, with MacPascal. We have around 30 Lisas 2/5's, used for the third course, with System V. I am not going to make detailed comments on the software. Our faculty are in a better position to do that. I can comment mostly on the general logistics of handling over 1000 students. Our machines are distributed over 5 locations. All but one are attended, and are open until around 1am. The person attending them has other jobs, however, like distributing printout, and handling questions about our DEC-20's and other machines. The largest site is at the computer center, and is open all the time. It is not attended. We have secured the machines using glue-on pads. (They come in two pieces, which glue to the bottom of the machines and the table. They are held together by rods which are held in with a lock.) So far we have not lost any machines, but have lost 2 mice at the unattended site. (We generally do not have much of a security problem. We normally leave terminals in open rooms without securing them, and have had very little trouble.) Our major hardware problem is with diskettes getting "eaten". Several of our Lisas eat diskettes. That is, suddenly your files are not readable. Unfortunately, our students are not always able to determine which machine is causing the trouble, except in extreme cases. So we don't know the exact number that are causing trouble. It looks like around 4. One of our biggest headaches is the fact that there is no way to check alignment of a drive. We are trying to get Apple to send in a level 2 service person to do this. The claim is that it will take 5 hours per drive. It is hard to believe that we can't figure out which ones are bad, but we really can't. By the time the damage is noticed, it is not clear where it was caused. We seem to have the same problem with the Macs. One of them (the first one we tried) had this in a fairly reproducible form. After using Pascal in it for a few days, the disk would become unbootable. Of the public Macs, we are quite sure that we have one bad drive (though we don't know which), and suspect that there are a few others. So somewhere between 2 and 6 out of 60 seem to have been bad. Otherwise, the hardware has been good. We have had a Profile failure or two, and a couple of other infant mortalities on the Lisas, but the Macs have not had any other problems that I can recall. I was concerned that the Imagewriters would not stand up to student use. We have two at each site, one for the Lisas and one for the Macs. (total of 6). We have had one failure so far, which isn't bad considering our past experience with micro printers. Now we come to the logistics. We were unable to get copies of MacPascal for each student. There are two problems here. One is pricing. We don't think a public institution can require students to pay > $100 for software for a required course. Apple agrees, and we expect to see a special deal for use in courses. However there have been infinite delays in getting those arrangements made. Even now, although apparently everybody agrees on the terms, there is no final program. The best suggestion so far is that they will sell the regular package for $75, and we can distribute the 2 system disks to 2 separate students, for a cost of $37.50. We think that is still a bit too high, but there are also some slight problems, like the fact that there is only one set of manuals, and the fact that we don't want to be responsible for any bad diskettes that might turn up. (Apparently the students would have to come to us if they had problems, and it would not be clear that we could get Apple to replace the diskettes.) But when we tried to do that, it turned out that they simply had not made enough Pascal diskettes, and could not do so in time to be of any use. For this fall, Apple has loaned us one copy of Pascal per machine (plus some extras in case of damage). We then have the students check them out, leaving behind I.D. cards. This is fine at the sites that have humans there all the time, but for the one that is open 24 hours a day, we have had to hire a new set of students to handle this. And students still don't always return them on time. It has been an infinite hassle, and has the students, the faculty, and two different pieces of the computer center yelling at each other. (The students don't know this, but it also turns out that the University will not authorize us to do anything about students who abuse the system.) We have been assured that for the Spring, there will be packages that each student can buy. We certainly hope so, because we won't survive this arrangement again. We would like to put Pascal on the Sunol network (the only network we have heard of so far). Everyone at Apple and Think is very interested and helpful, but among themselves they can't get anywhere with a licensing agreement to allow this. We suspect that this problem will not be solved until a year or so after Apple themselves has a network. We would be very interested in hearing from other schools that want to put their software on a network. Apple claims that they have heard little demand for this, and none of it representing people who need it immediately, as we do. We regard this as the only practical way to give students access to the software, and will do it within a few days of when it becomes technically and legally feasiable. I have a general comment on Mac Pascal. The Mac user interface is very sexy. It is not so clear that students find it easy to use. From watching students, I would say that they find it a bit more confusing than Tops-20. (These are students who have not seen Tops-20 before.) And much as I hate to say it, from past experience at U. of Illinois, I would say that students generally find the old Call-OS or CDC NOS interfaces easier to pick up than Tops-20. (For those who don't remember Call-OS: it was a time sharing system that looked like a typical BASIC top-level. OLD, NEW, SAVE, and RUN, and you retyped a line to change it.) Our situation is complicated by the fact that students are sharing diskettes. It is amazing how many things you can do to a MacPacal diskette. They change the background (and all other preferences options), remove Pascal from the desktop (doesn't do any harm, but the next student may not be able to find it - and of course once you have removed it, copy protection won't let you move it back on in the obvious way. a really wierd feature.), and even edit the print program so it does slightly strange things. (It is supplied in source form.) We can't write protect the diskettes because there is a bug in MacPascal that prevents us from keeping all the students' programs on a separate diskette. Thus they have to copy them to the Pascal diskette, play with them, and then copy them back. (The bug is that Pascal doesn't always check whether the right diskette is in the drive, so it sometimes blows up if you try to run when you have the student's diskette in the drive.) Certainly these problems will go away next semester, assuming that the students do each have their own copy. The students all hate System V. First, you should understand that Rutgers hasn't used Unix in the past. After Tops-20, it is a great shock. So there is a bit of bias against Unix here. But that isn't all. The biggest problem is the Profiles. We bought them because (like most universities) money is limited. They have enough capacity for our purposes. But they are ssssllllloooowwww. An ls command seems to take forever, most of it time for the program to load. We do not see any performance difference between loading programs from hard disk vs. floppy. In fact by any objective standard, the time to do a command is perfectly reasonable (about 7 sec. to do an ls). But is is slow enough to make the system feel painful. We have also had problems that are just learning-curve things. E.g. we didn't tell the students that they should save any of their ac's that had useful information before calling printf. We didn't say it partly because I figured the faculty would mention in class that you normally save AC's when calling library routines that don't specifically say otherwise. Also, partly because we didn't have time to try things out very much before the semester started. And our graphics routines don't work. It seems that in the first week of class we found that system V was mysteriously crashing on machines that had printers. We got a new release of the kernel that fixed this. What they didn't tell us was that this release changed the address to which the screen was mapped. On a timesharing system this would be trivial. But we had 30 machines at 4 locations, each with their own copy of the software. This sort of thing will be OK next semester, because we will know more about the sytsem and have more time to prepare. This will still leave us with the "#$'&% slow Profiles, though. The only thing I can think of to do there is use RAM disk. As we have no source nor internal documentation, we aren't going to be able to, but if anyone hears of a RAM disk for the Uniplus System V, I'd love to hear it. (PS: one of our staff has a Lisa with a Corvus disk. Aside from the fact that the Corvus disk has failed a few times, he loves it. The problem is strictly with the slowness of the Profile.) Apple's support has been of varying quality. I am sure they believe that they moved heaven and earth to get us the hardware and software in time for class to start. And in fact they did. Just barely. However we ordered it in late Spring. The delay was because of attempts to negotiate a University-wide discount program. I won't bore you with the details, beaause it is not clear to me whether it was Apple or Rutgers slowing things down. But the evidence does suggest that you shouldn't hold your breath while negotiating any sort of unusual contract with Apple. The problem is that except for that one initial shipment, everything else has required us to call our salesman several times, and her to call the regional support center several times. We still don't have printer ribbons. We have been buying them locally, 24 hours before each assignment. (We didn't do them in advance, because we were told that the ones from Apple were in the mail.) We now hear that they are on backorder (and Apple suspects that the next time we try to get them locally we will fail there too). We still don't have a copy of Inside Mac. It's really great to hear all the neat stuff the rest of you have been doing. We wish we could do development too. We were just notified that there had been a price decrease in Inside Mac. Our origianl order (made this summer) has been cancelled so we can order again at the lower price. Gee, thanks, guys. One of our grad students has just become a certified developer. We are hoping that this will give us access to Inside Mac. We find that Apple hasn't yet figured out that mice may disappear. We would like to keep a few spares, so that we can have the operators swap out ones that need to be cleaned, and replace ones that walk away. We can't order them, because only level 1 service centers can order them. It now appears that we can get a local dealer to front for us in replacing stolen mice. But it appears we still can't keep spares on site. I guess we are going to become a level 1 center, but the whole point of all this was supposed to be to make it easy on the customer, not to require him to turn himself into a dealer. We are also frustrated by not being able to get diagnostics. We don't want to fix anything. But we do want to be able to figure out which Macs have misaligned disk drives. However now it seems that the dealers can't check alignment either, so I guess we shouldn't feel discriminated against. We think that Apple's policies about not giving customers access to support resources are a bad idea. They force the sophisticated customers to become level 1 authorized. This does not serve to protect the dealers. We don't want to replace our local dealer, but we may be forced to. I'm sure these problems will all be cleared up within 6 months or so. But the result has been a very unpleasant fall. In case anyone wonders why we did this, I think we didn't have a lot of choice. We were using a similar number of Terak micros. They were failing more and more often. Spares were no longer available on some parts. And our technician quit. It seems clear that we would not have survived the fall using the Teraks. Our specs required a student-oriented Pascal, a machine with a decent instruction set, and a symbolic debugger. The Mac was the only thing (other than another Terak, and Terak didn't respond to our RFQ) that had an appropriate Pascal. Unix on a 68000 was the least expensive thing we could find that met the specs for the assembly language. (Our faculty do not consider the 8088 instruction set acceptable.) So we felt that this was a reasonable way to go. I'm not sure what we would have done if we had realized how it was going to turn out. Maybe we would have done the same thing anyway. -------