seb022@tijc02.UUCP (Scott Bemis ) (12/16/87)
I have currently installed two CDC 9772 disk drives with an Emulex SC7003
disk controller on a VAX 8600. This VAX 8600 is using the AT&T UNIX V
Release 2.0 Version 2 operating system. Carefully controlled bench-
marks showed these disk drives to be 43 percent faster than the RA81 disk
drives. Or other words, an extremely large make (compilation if you are not
familar with UNIX) took 5 hours 41 minutes using a RA81 disk drive to store the data.
When the data was stored upon the CDC 9772 disk drive, this exact (yes exact)
same make took 3 hours 12 minutes. The only difference was the disk drive and
disk controller. These benchmarks were used to determine if my company was
going to buy the CDC 9772 disk drives (which is why they were carefully
controlled). I have not had any problems with these disk drives, once
they were properly installed and had passed diagnostics. I did receive
one CDC 9772 disk drive that did not work. After spending one week on the
Emulex hotline, I finally convinced them that it did not work. They sent me
a replacement disk within 24 hours. Convincing them was the hard part.
And the Emulex technician did not install the Emulex SC7003 disk controller
correct the first time. DEC Field Service solved the problem. (Unfortunately,
this nonsense is too common for me). Below is an installation history
I presented to my company management.
Here is a brief history describing the installation of the Emulex SC7003
disk controller and the two CDC 9772 disk drives.
11/23/87
Scott Bemis
Installation history of the Emulex SC7003 disk controller
and two Control Data Corporation Model 9772 disk drives
on the UNIX VAX 8600
5/30/87 Received quote on disk controller and disk drives
6/5 - 6/18/87 Contacted several customers references, received good
4 references
6/26/87 Ordered two CDC disk drives and one SC7003 disk controller,
committed ship date from Emulex was 7/24
8/24 Received equipment from Emulex, VAX 8600 could not be
taken down due to the TISTAR release
10/9 Installed two CDC disk drives and SC7003 disk controller,
one disk drive did not work, power (AC/DC low) to the disk
controller was incorrectly connected, disk controller
would not work if power was turned off and on for the VAX
8600
10/16 DEC Field Service "rewired" the power (AC/DC low) per
Emulex instructions, can turn power off and on for VAX 8600,
and the disk controller will still work
10/23-10/26 Ran diagnostics to prove one CDC disk drive did not work
10/27 UNIX operating system can communicate with the CDC 9772
disk drives
10/29 Ran benchmarks on one good disk drive, CDC disk drive 43% faster
than the Digital Equipment RA81 disk drives
10/30 Replaced one CDC 9772 disk drive
10/31 Moved data to the two CDC disk drives
11/15 One CDC 9772 disk drive began to lose data, moved all data
off the failing CDC 9772 disk drive - this was the disk
drive that was replaced on 10/30
11/16-11/17 Ran diagnostics per Emulex's instructions. Discovered cause
of data loss on bad disk drive. The bad sector map file
was destroyed. But can not determine how this file was
destroyed - to prevent it from happening again.
11/23 Discovered that UNIX had overwritten the bad manufacture sector
file. Fixed problem, put data back upon the disk drive
If the above is not enough, then you can contact me. My telephone, mail
address, etc. is listed below.
Scott Bemis
Telephone: (615) 461-2959
Texas Instruments
P. O. Drawer 1255 M/S 3517
Johnson City, TN 37601
e-mail: mcnc!rti!tijc02!rootchris@mimsy.UUCP (Chris Torek) (12/17/87)
In article <182@tijc02.UUCP>, seb022@tijc02.UUCP (Scott Bemis) writes: >... Carefully controlled benchmarks showed these disk drives to be >43 percent faster than the RA81 disk drives. I am a little surprised they are only this much faster. I would attribute DEC RA drive slowness to the UDA50 if my measurements on a KDB50 did not show that it is not much faster. Part of the problem is the 6ms head switch delay in the RA81. -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690) Domain: chris@mimsy.umd.edu Path: uunet!mimsy!chris