Seagate Cheetah 18LP, Product Manual, Page: 19 / 94

Cheetah 18LP Product Manual, Rev. F 9
4.0 Performance characteristics
4.1 Internal drive characteristics (transparent to user)
4.2 SCSI performance characteristics (visible to user)
The values given in Section 4.2.1 apply to all models of the Cheetah 18LP family unless otherwise specified.
Refer to Section 9.10 and to the appropriate SCSI Interface Product Manual, for additional timing details.
4.2.1 Access time [5]
4.2.2 Format command execution time (minutes) [1]
4.2.3 Generalized performance characteristics
Data buffer transfer rate to/from disc media (one 512-byte sector):
SCSI interface data transfer rate (asynchronous):
Maximum instantaneous one byte wide 5.0 Mbytes/sec [4]
Maximum instantaneous two bytes wide 10.0 Mbytes/sec [4]
Synchronous transfer rate for SCSI Fast-40, Ultra2 SCSI (ST318203 and ST39103 models):
In single-ended (SE) interface mode 5.0 to 40 Mbytes/sec
In low voltage differential (LVD) interface mode 5.0 to 80 Mbytes/sec
ST318203 ST39103 ST318233 ST39133
Drive capacity 18.2 9.10 18.2 9.10 GByte (formatted, rounded)
Read/write heads 12 6 12 6
Bytes/track 153,284–
229,045 153,284–
229,045 153,284–
229,045 153,284–
229,045 Bytes (average, rounded)
Bytes/surface 1,913 1,913 1,913 1,913 Mbytes (unformatted, rounded)
Tracks/surface (total) 9,801 9,801 9,801 9,801 Tracks (user accessible)
Tracks/inch 12,580 12,580 12,580 12,580 TPI
Peak bits/inch 252 252 252 252 KBPI
Internal data rate 193-308 193–308 193-308 193–308 Mbits/sec (variable with zone)
Disc rotational speed 10,016 10,016 10,016 10,016 r/min (+0.5%)
Average rotational latency 2.99 2.99 2.99 2.99 msec
Including controller overhead
(without disconnect) [1] [3] Not including controller overhead
(without disconnect) [1] [3]
Drive level Drive level
Read Write Read Write
msec msec
Average – Typical [2] 5.4 6.0 5.2 5.8
Single Track – Typical [2] 0.7 0.9 0.5 0.7
Full Stroke – Typical [2] 12.2 13.2 12.0 13.0
ST318203/ST318233 ST39103/ST39133
Maximum (with verify) 60 60
Maximum (no verify) 30 30
Minimum sector interleave 1 to 1
Min. [3] 22.7 MByte/sec
Avg. [3] 29.5 MByte/sec
Max. [3] 36.2 MByte/sec