RLL and ESIX

[Piercarlo Grandi]

On 9 Nov 90 21:38:27 GMT, mike at atc.SP.Unisys.COM (Mike Grenier) said:

mike> I also have the Western Digital plain jane (WD1003-SR2) with my
mike> AMI bios but ESIX consistantly panics in the routine
mike> echd_read_vtoc() when booting the box after the tenth distribution
mike> floppy. My disk is somewhat bigger than yours, .i.e 250 meg. The
mike> S51K file system works fine.

This does not make much sense really. the vtoc reading routine is in the
driver, not in the filesystem. As far as things are supposed to be, the
WD and Adaptec RLL controllers and the WD MFM controller are absolutely
identical as far as the kernel is concerned. I think it would take some
deliberation to actually write code that could discerne among them
(except for the trivial issue of the # of sectors per track).

Your problems seem to be hardware related.

mike> Of course, my Adaptec 2372 disk controller wasn't supported at all
mike> with panics in the hdintr() routine.

This may well be hardware related as well. My own machine has to stay
turned on for half an hour before booting to warm up the controller and
the drive, otherwise horrible things will happen.

mike> The WD1006-SR2 can also panic when accessing the raw drive : .i.e
mike> use 2 drives and do a mkpart -v on the second one while compiling
mike> something big on the first.

This instead looks like an authentic bug, caused by not anticipating the
idea that a user may want to format disks while in multiuser mode.

mike> One thing I can say for Microport, my old UNIX System V/386
mike> Release 3.0e was rock solid on the same hardware.  You can guess
mike> which vendor will be supplying our UNIX V.4

But 3.0 (without the e) was quite buggy instead. Do not expect
consistency in these matters. Also, have a look at Dell's (or Intel's)
SVR4. If I understand correctly you can use your ESIX rev. D to get a
substantial discount on SVR4.
--
Piercarlo Grandi                   | ARPA: pcg%uk.ac.aber.cs at nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcsun!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg at cs.aber.ac.uk