ISC 3.2/harddisk & floppy problems

[Raymond Nijssen]

edhall at rand.org (Ed Hall) writes:
>In article <rcbarn.677172100 at rwc.urc.tue.nl> rcbarn at urc.tue.nl writes:
>>marzusch at odiehh.hanse.de (Ralph-Diether Marzusch) writes:
>>>     If you connect two (!) hard disk drives to one (ore even two) `standard'
>>>     AT type hard disk controller (i.e. MFM, RLL or ESDI drives) you may
>>>     experience a `hanging' disk controller (making any further disk accesses
>>>     impossible which possibly destroys one or more file systems) when both 
>>>     disks are accessed concurrently 

>It might be.  I've had infrequent but persistant lockup problems with
>ISC and a WD1006SR2 and a *SINGLE* disk.

Although does not sound like the problem the original poster addressed,
I'm very interested whether your controller has a chip with 'PROTO' on it,
as I've never heard of this problem. Could you please have a look?

>The clincher is that the lockup problem can happen with just a single disk.

>As you state, there is a relatively simple fix for the overlapping
>seek problem--simply disable overlapping seeks.  I wish that the
>solution for the lockup problem were so simple.

Well, it worked perfectly for me. I never experienced the second kind of 
lockups, even when I was running X on my system with just 4Mb,
swap partitions on both disks and huge, almost continuous swapping.
This is why I still believe that the solution for the lockup problem
is so simple. (For you info: without this fix, the system would
crash within two or three minutes after having started X).

I now have another WD1006Svr2 (whithout the infamous 'PROTO' message)
for some months, overlapped-seeks re-enabled, and the system has 
never paniced ever since.

-Raymond
-- 
| Raymond X.T. Nijssen  | Eindhoven Univ. of Technology                       |
| raymond at es.ele.tue.nl | EH 7.13, PO 513, 5600 MB Eindhoven, The Netherlands |
| "Don't put that on the wall in a tax-payer supported museum!"  Pat Buchanan |