[fa.info-vax] uVAX disk controller warning

info-vax@ucbvax.ARPA (03/18/85)

From: Richard Garland <OC.GARLAND@CU20B.ARPA>

I have been told by one of our department's of a micro VAX-I disk 
controller problem (RQDX1) which they say was verified by RDC:

Each time you power on the uVAX, the disk controller flags a good block
as bad (My contact thought the particular block was random).

This has 2 effects:

	1) The disk is slowly but surely renderred unusable as your files
	get corrupted.

	2) Even if the good-bad blocks are not in files, performance
	degrades due to the other more well known problem with the
	controller:  The controller microcode is so slow that after
	you get around 12 bad blocks to revector, you lose a whole revolution
	on each disk read or write (since it must look through the
	revectoring table each time.)

There is supposed to be a uCode update to fix the false bad block
problem.  Meantime, don't turn off your microVAXen, and make sure
field service knows you need/want the controller micro-code fix.

					Rg
-------

info-vax@ucbvax.ARPA (03/29/85)

From: Dustin.MAVDVAX@HI-MULTICS.ARPA

An entry dated 3/18/85 from garland warned of a uVAX disk controller
problem.  I called our local DEC service office and they have no record
of this problem.  In order for them to track the problem, they need more
information such as the RDC contact person and if there is a number
associated with it.

Please forward information to this forum or contact Joni Dustin (612)
542-4223.

Thank You!