vandys@hpindda.HP.COM (Andy Valencia) (05/25/88)
This isn't mine; I'm just posting it for Mr. Zorat.... Andy From mcvax!irst!zorat@uunet.UU.NET Mon May 23 23:46 PDT 1988 Received: from hplabs.HP.COM by hpindda.HP.COM; Mon, 23 May 88 23:46:33 pdt Received: from uunet.UU.NET by hplabs.HP.COM with SMTP ; Mon, 23 May 88 20:55:46 PST Received: from mcvax.UUCP by uunet.UU.NET (5.54/1.14) with UUCP id AA08707; Tue, 24 May 88 00:55:25 EDT Received: by mcvax.cwi.nl; Mon, 23 May 88 18:39:37 +0200 (MET) Received: from irst.UUCP by i2unix.UUCP; Mon, 23 May 88 17:15:52 DST Received: by caneva.irst.it (3.2/SMI-3.2) id AA13089; Mon, 23 May 88 16:47:02 +0200 Date: 23 May 1988 16:34-EST From: mcvax!irst!zorat@uunet.UU.NET (Alessandro Zorat) Subject: Re: microport memory To: vandys@hpindda.hp.com (Andy Valencia) Message-Id: <580401278/zorat@caneva> Status: R Hello: I have been reading the problems that people are experiencing with the installation of uPort 386. I have had a terrible time with mine, on a Compaq portable 386. It boots and runs, but so slowly that it cannot even be used. I had prepared the following article to post and ask for advise, but we have just joined the net-news and for some reason on our site I cannot do a posting yet. Our manager tells me that he will have to recompile and allow posting permissions, but he has not done so yet. Could I please ask you to post my article for me and redirect any suggestions (if any) that might come out of this? Here is the article. Newsgroups: comp.unix.questions,comp.unix.microport Title: microport 386 and Compaq 386/20 I have installed (sucessfully) microport unix 386 Rel. 3.0 L2.2 on a portable Compaq 386/20 with a 40 Mbyte hard disk (type 17: 17 sect/track, 5 heads/cyl, 512 Bytes/sect., about 28 msec average seek time - the standard disk for the portable Compaq). The computer has 2 Mbyes of memory (of which only the bottom 640K of the base memory and the 1M of ty extended memory are seen by unix). The system installed OK, but it runs **exceedingly** slowly, so slow - in fact - as to make it unusable. I have traced the problem to a very slow transfer rate from the hard disk; the CPU is running at the prescribed speed (as tested by running a CPU-only, no disk I/O program.) The test I have tried to see the speed of the disk is: time dd if=/dev/rdsk/0s0 of=/dev/null bs=17b count=100 that is, read 100 tracks. The result was that the microport unix 386 took (elapsed time) a whopping 35 seconds!! (corresponding to a transfer rate of something like 25 Kbytes/sec. or thereabouts) On the same disk (on another partition) I have installed SCO xenix, also for the 386: on that the same test (reading 100 tracks from /dev/rdsk/hd00) takes only 5-6 seconds (as it should). Finally, I have also installed microport unix 286 and that shows a perfomance of about 7 seconds. The disk has been low level formatted (using the DOS utility "diskprep") with a 1:1 interleaving - and was left that way for the three systems on which I did my tests (Microport 386, SCO xenix 386 and Microport 286). Just to be safe, I have also tried to (low-level) format the hard disk with an interleaving factor of 3:1, but the Microport 386 showed exaclty the same performance. As a matter of fact, the DOS utility "spintest" showed always a transfer rate of about 256 Kbytes/sec and two disk revolutions necessary to read in a track, NO MATTER WHAT the interleaving factor was. This makes me suspect that the controller of the disk has the interleaving factor hardwired in and that it cannot be changed. But anyway, this does not explain - in my opinion - why transfer times on the SAME disk - take about 5-7 sec under xenix and 286 microport and 35 sec. under 386 microport. I have tried to set up uPort as the only system (no DOS, no other partitions), I have tried the 3:1 interleaving, and any other possibility that came to mind. I have run out of things to try; I have asked for assistance from Compaq and Microport, but I have not obtained any suggestions of what to do (or of what to try) next. As a matter of fact. Microport told me that they were not able to recreate my problem. I even got an other Compaq 386 just like mine, straight out of the box and installed uport on that: same problem. If anybody has a computer+system like mine and knows what is going on, I would appreciate very much hearing from you. Thanx in advance. My E-mail address is (should be ??) mcvax!irst!zorat@uunet.UU.NET