[comp.unix.wizards] Emulex UD33 - DEC UDA50

ncbergst@ndsuvax.UUCP (Troy Bergstrand) (07/14/88)

We just installed Emulex's UD33 disk controller on our VAX 780.  But 
unfortunately the installation did not complete without incident.

Our configuration:

Vax 11-780 12 Megabytes of memory 2 Unibus controllers
Unibus 1: UDA33 - 2 RA81, Interlan Ethernet Controller
Unibus 2: 11 DMF32's, 1  DH

We are running 4.3BSD Unix with no modifications to the uda or unibus code.

We desired to put both the UD33 and the UDA50 on the same unibus, Emulex
tells us this should work, but it didn't.  After setting the UDA50 jumpers
to the longest possible (10ms) DMA delay and setting the UD33 in the same
way and also reconfiguring the kernel to place the UD33 at different
unibus addresses we also got the same result.

That result was a hanging of the system on disk i/o.  I could run 
systat -vm and watch the disk requests and after a period of time there
would arise some situation where at least one of the disk requests would
not or could not be serviced.  After which near every other process on
the system would get stuck in the request queue behind the hung process.

So to get the new drive working we put the UD33 on the unibus 2 with the
communcation controllers and everything is ok there.

Has anyone succesfully installed a UD33 on a 4.3BSD unix system on the 
same unibus as an UDA50?
-- 
J. Troy Bergstrand      North Dakota State University,  Fargo, ND  58105
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chris@mimsy.UUCP (Chris Torek) (07/23/88)

In article <1030@ndsuvax.UUCP> ncbergst@ndsuvax.UUCP (Troy Bergstrand) writes:
>We are running 4.3BSD Unix with no modifications to the uda or unibus code.

>We desired to put both the UD33 [a UDA50 emulator] and the UDA50 on the
>same unibus, Emulex tells us this should work, but it didn't. ...
>result was a hanging of the system on disk i/o. ...

I used to have a similar problem on a 780 with two UDA50s, and someone
at Bell Labs had one with an 8600 with three of them.  After installing
my driver (which is included with 4.3BSD-tahoe) the problem disappeared.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris

chris@mimsy.UUCP (Chris Torek) (07/24/88)

In article <12655@mimsy.UUCP> I wrote:
>I used to have a similar problem [machine hangs waiting for I/O] on a 780
>with two UDA50s ....

I should have mentioned that the problem sometimes appeared to be that
the RA81s on one of the UDA50s would go off-line spontaneously.  This
can be seen as the `A' or `B' light on the drive going out.  Other
times, the UDA50 itself would hang.  This shows as an interruption in
the regular light pattern on one of the two Unibus modules (the usual
pattern is one light on, one blinking; the blinking would stop, as I
recall).  Since then the microcode on the UDA50 has been revised.
(Current microcode appears as `version 5 model 6' in printouts from my
driver.  I believe the off-line bug was fixed in version 4, and the
hang bug in version 5, or something like that.)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris