I'm presently evaluating an IBM Deskstar 18 disk drive, and not getting
the kind of performance I'd expect. The drive has produced read rates of
10 to 15 MB/sec on a P-II PC, but the fastest DISKX got on my Alpha was
4.24 MB/sec reading, and a painful 236.45 KB/sec writing. The drive is
the only device on the bus. The configuration:
AlphaStation 250 4/266, 96 MB memory
Digital Unix V4.0B (Rev. 564) with Jumbo Patch 5
2 GB Quantum system disk, CD, external 8mm tape drive on built-in SCSI
KZPSA FWD SCSI interface, ~1 meter cable
IBM DGHS18U FWSE drive with Rancho Diff-to-Single-Ended convertor
I was able to set up partitions on the drive, make ADVfs file systems,
copy my usual partitions to the drive, boot from it, etc, etc. It all
works fine, but just not as fast as I'd expect. I assume that we're not
achieving synchronous mode, or some other similar problem. Can you give
me any pointers on what I may have done wrong or failed to do? Or am I
stuck with mediocre performance?
I've included some additional details below, FWIW. Thanks for listening!
Cheers,
Wayne
baisley_at_fnal.gov
http://www-oss.fnal.gov/~baisley
SCU list of devices:
Device: XP32150 Bus: 0, Target: 0, Lun: 0, Type: Direct Access
Device: RRD43 Bus: 0, Target: 4, Lun: 0, Type: Read-Only Direct Access
Device: EXB-850085QANXRC Bus: 0, Target: 5, Lun: 0, Type: Sequential Access
Device: DGHS18U Bus: 1, Target: 5, Lun: 0, Type: Direct Access
SCU Inquiry Information for the drive:
SCSI Bus ID: 1
SCSI Target ID: 5
SCSI Target LUN: 0
Peripheral Device Type: 0 (Direct Access)
Peripheral Qualifier: 0 (Peripheral Device Connected)
Device Type Modifier: 0
Removable Media: No
ANSI Version: 3 (Complies to ANSI X3.xxx-199x, SCSI-3)
ECMA Version: 0
ISO Version: 0
Response Data Format: 2 (SCSI-2)
Terminate I/O Process: 0
Asynchronous Notification: 0
Additional Length: 159
Soft Reset Support: No
Command Queuing Support: Yes
Target Transfer Disable: No
Linked Command Support: Yes
Synchronous Data Transfers: Yes
Support for 16 Bit Transfers: Yes
Support for 32 Bit Transfers: No
Relative Addressing Support: No
Vendor Identification: IBM
Product Identification: DGHS18U
Firmware Revision Level: 0210
# disklabel -t advfs -rw rz13 scsi "IBM DGHS18U" /mdec/rzboot.advfs /mdec/bootrz.advfs
# disklabel -r rz13
type: SCSI
disk: DGHS18U
label: IBM DGHS18U
flags: dynamic_geometry
bytes/sector: 512
sectors/track: 280
tracks/cylinder: 20
sectors/cylinder: 5600
cylinders: 8154
sectors/unit: 35843670
rpm: 7200
interleave: 1
trackskew: 28
cylinderskew: 72
headswitch: 0 # milliseconds
track-to-track seek: 0 # milliseconds
drivedata: 0
8 partitions:
# size offset fstype [fsize bsize cpg]
a: 261600 0 unused 0 0 # (Cyl. 0 - 46*)
b: 523200 261600 swap # (Cyl. 46*- 140*)
c: 35843670 0 unused 0 0 # (Cyl. 0 - 6400*)
d: 0 0 unused 0 0 # (Cyl. 0 - -1)
e: 0 0 unused 0 0 # (Cyl. 0 - -1)
f: 0 0 unused 0 0 # (Cyl. 0 - -1)
g: 35058870 784800 unused 0 0 # (Cyl. 140*- 6400*)
h: 17725227 18118443 unused 0 0 # (Cyl. 3235*- 6400*)
Received on Sat Feb 14 1998 - 18:02:54 NZDT