Seagate ST3300655SS, ST3146855SS, ST373455SS, ST373455SSIM User Manual

Product Manual
Cheetah 15K.5 SAS
ST3300655SS ST3146855SS ST373455SS
100384784 Rev. E August 2007
©2007, Seagate Technology LLC All rights reserved.
Publication number: 100384784, Rev. E
August 2007
Seagate, Seagate Technology and the Wave logo are registered trademarks of Seagate Technology LLC in the United States and/or other countries. Cheetah, SeaTools and SeaTDD are either trademarks or reg­istered trademarks of Seagate Technology LLC or one of its affiliated companies in the United States and/ or other countries. All other trademarks or registered trademarks are the property of their respective own­ers.
One gigabyte, or GB, equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment and formatting. Quantitative usage examples for various applications are for illustrative purposes. Actual quantities will vary based on various factors, including file size, file format, features and application software. Seagate reserves the right to change, without notice, product offerings or specifications.
Cheetah 15K.5 SAS Product Manual, Rev. E
i
Contents
1.0 Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.0 Standards, compliance and reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1 Electromagnetic compatibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2.1 Electromagnetic compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 European Union Restriction of Hazardous Substances (RoHS) . . . . . . . . . . . . . . . . . . . . . 4
2.4 Reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.0 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1 Standard features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2 Media description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.4 Reliability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.5 Formatted capacities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.6 Programmable drive capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.7 Factory-installed accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.8 Options (factory installed) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.9 User-installed accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.0 Performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1 Internal drive characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2 Seek time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2.1 Access time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2.2 Format command execution time (minutes) . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2.3 General performance characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.3 Start/stop time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4 Prefetch/multi-segmented cache control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.5 Cache operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.5.1 Caching write data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.5.2 Prefetch operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.0 Reliability specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1 Error rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1.1 Recoverable Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1.2 Unrecoverable Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1.3 Seek errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.1.4 Interface errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.2 Reliability and service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.2.1 Mean time between failure (MTBF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.2.2 Preventive maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.2.3 Hot plugging the drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.2.4 S.M.A.R.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.2.5 Thermal monitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.2.6 Drive Self Test (DST). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.2.7 Product warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.0 Physical/electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.1 AC power requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.2 DC power requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.2.1 Conducted noise immunity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6.2.2 Power sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6.2.3 Current profiles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6.3 Power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
ii
Cheetah 15K.5 SAS Product Manual, Rev. E
6.4 Environmental limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.4.1 Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.4.2 Relative humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.4.3 Effective altitude (sea level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.4.4 Shock and vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.4.5 Air cleanliness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
6.4.6 Corrosive environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
6.4.7 Acoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
6.4.8 Electromagnetic susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
6.5 Mechanical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
7.0 Defect and error management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7.1 Drive internal defects/errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7.2 Drive error recovery procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7.3 SAS system errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7.4 Background Media Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7.5 Media Pre-Scan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7.6 Deferred Auto-Reallocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
7.7 Idle Read After Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
8.0 Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.1 Drive orientation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.2 Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.3 Drive mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
8.4 Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.0 Interface requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.1 SAS features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.1.1 task management functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.1.2 task management responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 Dual port support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
9.3 SCSI commands supported. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
9.3.1 Inquiry data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.3.2 Mode Sense data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.4 Miscellaneous operating features and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
9.4.1 SAS physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
9.4.2 Physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.4.3 Connector requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.4.4 Electrical description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
9.4.5 Pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
9.4.6 SAS transmitters and receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
9.4.7 Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
9.5 Signal characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
9.5.1 Ready LED Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
9.5.2 Differential signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
10.0 Seagate Technology support services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Cheetah 15K.5 SAS Product Manual, Rev. E
1
List of Figures
Figure 1. Cheetah 15K.5 SAS disc drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Figure 2. Typical ST3300655SS drive +12V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Figure 3. Typical ST3300655SS drive +5V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Figure 4. Typical ST3146855SS drive +12V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Figure 5. Typical ST3146855SS drive +5V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Figure 6. Typical ST373455SS drive +12V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Figure 7. Typical ST373455SS drive +5V current profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Figure 8. ST3300655SS (3 Gbit) DC current and power vs. input/output operations per second . . . . . . . . . . . . . . . . .29
Figure 9. ST3146855SS (3 Gbit) DC current and power vs. input/output operations per second . . . . . . . . . . . . . . . . .30
Figure 10. ST373455SS (3 Gbit) DC current and power vs. input/output operations per second . . . . . . . . . . . . . . . . . .31
Figure 11 . Loca tion of the HDA te mp e r a ture check poi n t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Figure 12. Recommended mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Figure 13 . Physical dimensi o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Figure 14 . Physical interfa ce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Figure 15 . Air fl o w . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Figure 16 . Physi cal interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
Figure 17. SAS connector dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
Figure 18. SAS connector dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
Figure 19. SAS transmitters and receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
Figure 20 . Rec e i ve e ye ma sk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Figure 21 . Rec e i ve to l e r a n ce e ye ma sk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Figure 22 . Sin u so i d a l j i tte r ma sk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Figure 23. Compliance interconnect test load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
Figure 24. Zero-length test load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Figure 25 . ISI loss example at 3.0 G b p s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Figure 26 . ISI loss example at 1.5 G b p s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
2
Cheetah 15K.5 SAS Product Manual, Rev. E
Cheetah 15K.5 SAS Product Manual, Rev. E
1

1.0 Scope

This manual describes Seagate Technology® LLC, Cheetah® SAS (Serial Attached SCSI) disc drives. Cheetah drives support the SAS Protocol specifications to the extent described in this manual. The SAS Inter-
face Manual (part number 100293071) describes the general SAS characteristics of Cheetah 15K.5 and other Seagate SAS drives.
Figure 1. Cheetah 15K.5 SAS disc drive
2
Cheetah 15K.5 SAS Product Manual, Rev. E
Cheetah 15K.5 SAS Product Manual, Rev. E
3

2.0 Standards, compliance and reference documents

The drive has been d evelope d as a system p eriphe ral to the hig hest st and ards of desig n and constru c tion. The drive depends on its host equipment to provide adequate power and environment for optimum performance and compliance with applicable industry and governmental regulations. Special attention must be given in the areas of safety, power distribution, shielding, audible noise control, and temperature regulation. In particular, the drive must be securely mounted to guarantee the specified performance characteristics. Mounting by bot­tom holes must meet the requirements of Section 8.3.

2.1 Standards

The Cheetah SAS family complies with Seagate standards as noted in the appropriate sections of this manual and the Seagate SAS Interface Manual, part number 100293071.
The Cheetah disc driv e is a UL recognize d compo nent per UL 1950 , CSA certifi ed to CAN /CSA C22.2 N o. 95 0­95, and VDE or TUV certified to EN60950.

2.1.1 Electromagnetic compatibility

The drive, as delivered, is designed for system integration and installation into a suitable enclosure prior to use. The drive is supplied as a subassembly and is not subject to Subpart B of Part 15 of the FCC Rules and Regulations nor the Radio Interference Regulations of the Canadian Department of Communications.
The design characteristics of the drive serve to minimize radiation when installed in an enclosure that provides reasonable shielding. The drive is capable of meeting the Class B limits of the FCC Rules and Regulations of the Canadian Department of Communications when properly packaged; however, it is the user’s responsibility to assure that the drive meets the appropriate EMI requirements in their system. Shielded I/O cables may be required if the enclosure does not provide adequate shielding. If the I/O cables are external to the enclosure, shielded cables should be used, with the shields grounded to the enclosure and to the host controller.
2.1.1.1 Electromagn etic susc ept ibili ty
As a component assembly, the drive is not required to meet any susceptibility performance requirements. It is the responsibility of those integrating the drive within their systems to perform those tests required and design their system to ensure that equipment operating in the same system as the drive or external to the system does not adversely affect the performance of the drive. See Tables 2, 3 and 4, for DC power requirements.
4
Cheetah 15K.5 SAS Product Manual, Rev. E

2.2 Compliance

2.2.1 Electromagn etic complia nce

Seagate uses an independent laboratory to confirm compliance with the directives/standards for CE Marking and C-Tick Marking. T he dr ive was tested in a r epre sent ative system for typica l applications. The select ed sys­tem represents the most popular characteristics for test platforms. The system configurations include:
• Typical current use microprocessor
• 3.5-inch floppy disc drive
• Keyboard
• Monitor/display
•Printer
• External modem
•Mouse Although the test system with th is Seag ate mo del comp lies with the dir ectives/st and ards, we cannot gu aran tee
that all systems will comply. The computer manufacturer or system integrator shall confirm EMC compliance and provide the appropriate marking for their product.
Electromagnetic compliance for the European Union
If this model has the CE Marking it complies with the European Union requirements of the Electromagnetic Compatibility Directive 89/336/EEC of 03 May 1989 as amended by Directive 92/31/EEC of 28 April 1992 and Directive 93/68/EEC of 22 July 1993.
Australian C-Tick
If this model has the C-Tick Marking it complies with the Australia/New Zealand Standard AS/NZS3548 1995 and meets the Electromagnetic Compatibility (EMC) Framework requirements of Australia’s Spectrum Man­agement Agency (SMA).
Korean MIC
If this model has the Korean Min ist ry of Infor mat ion and Com munication (MIC) logo, it complie s with par agr aph 1 of Article 11 of the Electromagnetic Compatibility (EMC) Control Regulation and meets the Electromagnetic Compatibility Framework requirements of the Radio Research Laboratory (RRL) Ministry of Information and Communication Republic of Korea.
Taiwanese BSMI
If this model has two Chinese words meaning “EMC certification” followed by an eight digit identification num­ber, as a Marking, it complies with Chinese National Standard (CNS) 13438 and meets the Electromagnetic Compatibility (EMC) Framework requirements of the Taiwanese Bureau of Standards, Metrology, and Inspec­tion (BSMI).

2.3 European Uni on Restric tion of Hazardous Substances (RoHS)

The European U nion Restr icti on of Hazard ous S ubst ance s (RoHS ) Dire cti ve re strict s the p resen ce of ch emic al substances, including Lead (Pb), in electronic products effective July 2006.
A number of parts and materials in Seagate products are procured from external suppliers. We rely on the rep­resentations of our suppliers regarding the presence of RoHS substances in these parts and materials. Our supplier contracts require compliance with our chemical substance restrictions, and our suppliers document their compliance wi th our re quire ment s by providing material conte nt declar ations for al l par ts an d mater ial s for the disc drives documented in this publication. Current supplier declarations include disclosure of the inclusion of any RoHS-regulated substance in such parts or materials.
Cheetah 15K.5 SAS Product Manual, Rev. E
5
Seagate also has internal system s in place to en sure ongoing complian ce with the RoHS Directive and all laws and regulations which restrict chemical conte nt in electron ic produ cts. T hese system s include sta ndar d operat­ing procedures that ensure that restricted substances are not utilized in our manufacturing operations, labora­tory analytical validation testing, and an internal auditing process to ensure that all standard operating procedures are complied with.

2.4 Reference documents

Cheetah 15K.5 SAS Installation Guide Seagate part number: 100384785 SCSI Commands Reference Manual Seagate part number: 100293068 SAS Interface Manual Seagate part number: 100293071 Applicable ANSI SAS documents
SFF-8323 3.5” Drive Form Factor with Serial Connector SFF-8460 HSS Backplane Design Guidelines SFF-8470 Multi Lane Copper Connector SFF-8482 SAS Plug Connector ANSI INCITS.xxx Serial Attached SCSI (SAS) Standard (T10/1562-D) ISO/IEC 14776-xxx SCSI Architecure Model-3 (SAM-3) Standard (T10/1561-D) ISO/IEC 14776-xxx SCSI Primary Commands-3 (SPC-3) Standard (T10/1416-D)
ISO/IEC 14776-xxx SCSI Block Commands-2 (SBC-2) Standard (T10/1417-D) ANSI Small Computer System Interface (SCSI) Documents X3.270-1996(SCSI-3) Architecture Model Specification for Acoustic Test Requirement and Procedures Seagate part number: 30553-001 Package Test Specification Seagate P/N 30190-001 (under 100 lb.) Package Test Specification Seagate P/N 30191-001 (over 100 lb.)
In case of conflict between this document and any referenced document, this document takes precedence.
6
Cheetah 15K.5 SAS Product Manual, Rev. E
Cheetah 15K.5 SAS Product Manual, Rev. E
7

3.0 General description

Cheetah drive s combin e Tunneling Ma gneto resistive (T M R) head s and a Ser ial Attached SCSI (SAS) interface to provide high pe rfor mance , high cap acity d at a sto rage for a va riety o f system s includ ing en gineer ing worksta­tions, network servers, mainframes, and supercomputers. The Serial Attached SCSI interface is designed to meet next-generation computing demands for performance, scalability, flexibility and high-density storage requirements.
Cheetah drives are random access storage devices designed to support the Serial Attached SCSI Protocol as described in the ANSI specifications, this document, and the SAS Interface Manual (part number 100293071) which describes the general interface characteristics of this drive. Cheetah drives are classified as intelligent peripherals and provide level 2 conformance (highest level) with the ANSI SCSI-1 standard. The SAS connec­tors, cables and electrical interface are compatible with Serial ATA (SATA), giving future users the choice of populating their syste ms with eithe r S AS or SATA har d d isc dr ives. This allo ws you to continue to levera ge yo ur existing investment in SCSI while gaining a 3Gb/s serial data transfer rate.
The head and disc assembly (HDA) is sealed at the factory. A ir recirculates within the HDA through a non­replaceable filter to maintain a contamination-free HDA environment.
Note. Never disassemble the HDA and do not attempt to service items in the sealed enclosure (heads,
media, actuator, etc.) as this requires special facilities. The drive does not contain user-replaceable parts. Opening the HDA for any reason voids your warranty.
Cheetah drives use a de dicated landing zone a t the innermost radius of the media to e liminate the p ossibility of destroying or de grad i ng d at a b y l and ing in the data zone. Th e h eads autom atical ly go t o the landing zone when power is removed from the drive.
An automatic shipping lock prevents potential damage to the heads and discs that results from movement dur­ing shipping and handling. The shipping lock disengages and the head load process begins when power is applied to the drive.
Cheetah drives decode track 0 location data from the servo data embedded on each surface to eliminate mechanical transducer adjustments and related reliability concerns.
The drives also use a high-performance actuator assembly with a low-inertia, balanced, patented, straight arm design that provides excellent performance with minimal power dissipation.
8
Cheetah 15K.5 SAS Product Manual, Rev. E

3.1 Standard featu re s

Cheetah drives have the following standard features:
• 1.5 / 3 Gbit Serial Attached SCSI (SAS) interface
• Integrated dual port SAS controller supporting the SCSI protocol
• Support for SAS expanders and fanout adapters
• Firmware downloadable using the SAS interface
• 128 - deep task set (queue)
• Supports up to 32 initiators
• Jumperless configuration.
• User-selectable logical block size (512, 520, 524, or 528 bytes per logical block)
• Perpendicular recording technology
• Programmable logical block reallocation scheme
• Flawed logical block reallocation at format time
• Programmable auto write and read reallocation
• Reallocation of defects on command (Post Format)
• ECC maximum burst correction length of 320 bits
• No preventive maintenance or adjustments required
• Dedicated head landing zone
• Embedded servo design
• Automatic shipping lock
• Embedded servo design
• Self diagnostics performed when power is applied to the drive
• Zone bit recording (ZBR)
• Vertical, horizontal, or top down mounting
• Dynamic spindle brake
• 16 Mbyte data buffer (see Section 4.5).
• Drive Self Test (DST)
• Background Media Scan (BGMS)
• Power Save

3.2 Media desc ription

The media used on the drive has an aluminum substrate coated with a thin film magnetic material, overcoated with a proprietary protective layer for improved durability and environmental protection.

3.3 Performance

• Firmware-controlled multisegmented cache designed to dynamically adjust segments for enhanced system performance.
• 300 Mbytes/sec maximum instantaneous data transfers.
• 15k RPM spindle. Average latency = 2.0 msec
• Background processing of queue
• Supports start and stop commands (spindle stops spinning)
• Adaptive seek velocity; improved seek performance
Cheetah 15K.5 SAS Product Manual, Rev. E
9

3.4 Reliability

• 1,400,000 hour MTBF (Annualized Failure Rate (AFR) of 0.62%)
• Incorporates industry-standard Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.)
• 5-year warranty

3.5 Formatted ca pacities

Standard OEM models are formatted to 512 bytes per block. The block size is selectable at format time and must be a multiple of 4 bytes. Users having the necessary equipment may modify the data block size before issuing a format command and obtain different formatted capacities than those listed.
To provide a stable target capacity environment and at the same time provide users with flexibility if they choose, Seagate recommends product planning in one of two modes:
1. Seagate designs specify capacity points at certain block sizes that Seagate guarantees current and future products will meet. We recommend customers use this capacity in their project planning, as it ensures a stable operating point with backward and forward compatibility from generation to generation. The current guaranteed operating points for this product are:
Capacity (Blocks)
ST3300655SS ST3146855SS ST373455SS
Sector Size
Decimal Hex Decimal Hex Decimal Hex
512
585,937,500 22ECB25C 286,749,488 11177330 143,374,744 88BB998
520
573,653,847 22314357 280,790,184 10BC84A8 140,395,092 85E4254
524
566,007,800 21BC97F8 275,154,368 106685C0 137,577,184 83342E0
528
557,874,778 21407E5A 272,662,935 10408197 136,331,467 82040CB
2. Seagate drives also may be used at the maximum available capacity at a given block size, but the excess capacity above the guaranteed level will vary between other drive families and from generation to genera­tion, depending on how each block size actually formats out for zone frequencies and splits over servo bursts. This added capacity potential may range from 0.1 to 1.3 percent above the guaranteed capacities listed above. Using the drives in this manner gives the absolute maximum capacity potential, but the user must determine if the extra capacity potential is useful, or whether their assurance of backward and for­ward compatibility takes precedence.

3.6 Programmable drive capacity

Using the Mode Select command, the drive can change its capacity to something less than maximum. See the Mode Select (6) parameter list table in the SAS Interface Manual, part number 100293071. A value of zero in the Number of Blocks field indicates that the drive will not change the capacity it is currently formatted to have. A number other than zero and less than the maximum number of LBAs in the Number of Blocks field changes the total drive cap acity to the value in the Nu mber of Blocks field. A value gre ater t han th e maxim um nu mbe r of LBAs is rounded down to the maximum capacity.

3.7 Factory -installed acce ssories

OEM standard drives are shipped with the Cheetah 15K.5 SAS Installation Guide, part number 100384785, and the Safety and Regulatory Agency Specifications, part number 75789512 (unless otherwise specified).
10
Cheetah 15K.5 SAS Product Manual, Rev. E

3.8 Options (factory installed)

Yo u may order the following items which are incorporated at the manufacturing facility d uring production or packaged before shipping. Some of the options available are (not an exhaustive list of possible options):
• Other capacities can be ordered depending on sparing scheme and sector size requested.
• Single-unit shipping pack. The drive is normally shipped in bulk packaging to provide maximum protection against transit damage. U nit s shipped individually require add itional pro tection as pr ovided by th e singl e unit shipping pack. Users planning single unit distribution should specify this option.
• The Cheetah 15K.5 SAS Installation Guide, part number 100384785, is usually included with each standard OEM drive shipped, but extra copies may be ordered.
• The Safety and Regulatory Agency Specifications, part number 75789512, is usually included with each standard OEM drive shipped, but extra copies may be ordered.

3.9 User-ins talle d accessorie s

The following accessories are available. All kits may be installed in the field.
• Single-unit shipping pack.
Cheetah 15K.5 SAS Product Manual, Rev. E
11

4.0 Performance characteristics

This section provides detailed information concerning performance-related characteristics and features of Cheetah drives.

4.1 Internal drive characteristics

ST3300655SS ST3146855SS ST373455SS
Drive capacity 300.0 146.8 73.4 Gbytes (formatted, rounded off value) Read/write data heads 8 4 2 Tracks per surface (total) 74,340 74,340 74,340 Tracks (user accessible) Tracks per inch 125,000 125,000 125,000 TPI Peak bits per inch 890 890 890 KBPI Areal Density 110 110 110 Gbits/inch Internal data rate 960 to 1607 960 to 1607 960 to 1607 Mbits/sec (variable with zone) Disc rotation speed 15k 15k 15k RPM Avg rotational latency 2.0 2.0 2.0 msec
*One Gbyte equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment
and formatting.
**Rounded off value.
2
*,**

4.2 Seek time

See Section 9.4.1, "SAS physical interface" on page 57 and the SAS Interface Manual (part number
100293071) for additional timing details.

4.2.1 Access time

Not Including controller overhead Read Write
Average Typical 3.5 4.0 Single track Typical 0.2 0.4 Full stro ke Typical 6.8 7.5
1, 2
(msec)
1. Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as measured on a representative sample of drives.
2. Access to data = access time + latency time.
12
Cheetah 15K.5 SAS Product Manual, Rev. E

4.2.2 Format command execution time (minutes)

ST3300655SS ST3146855SS ST373455SS
Maximum (wi th verify) Maximum (without verify)
120 90 60
60 45 30
Execution time measured from receipt of the last byte of the Command Descriptor Block (CDB) to the request for a Status Byte Transfer to the Initiator (excluding connect/disconnect).

4.2.3 General performance characteristics

Sustainable disc transfer rate*:
Minimum 73 Mbytes/sec Maximum 125 Mbytes/sec
SAS Interface maximum instantaneous transfer rate 300 Mbytes/sec* per port
Logical block sizes
Default is 512-byte data blocks Sector sizes variable to 512, 520, 524, and 528 kbytes.
Read/write consecutive sectors on a track Yes
Flaw reallocation performance impact (for flaws reallocated at format time using the spare sectors per sparing zone reallocation scheme.)
Average rotational latency 2.0 msec
*Assumes system ability to support the rates listed and no cable loss.
(dual port = 600 Mbytes/sec*)
Negligible

4.3 Start/stop time

The drive accepts the commands listed in the SAS Interface Manual less than 3 seconds after DC power has been applied.
If the drive receives a NOTIFY (ENABLE SPINUP) primitive through either port and has not received a START STOP UNIT command with the START bit equal to 0, the drive becomes ready for normal operations within 20 seconds (excluding the error recovery procedure).
If the drive receives a START STOP UNIT command with the START bit equal to 0 before receiving a NOTIFY (ENABLE SPINUP ) pri mitive, the drive waits for a S TART STOP UNIT com mand wi th th e START bit equal to 1. After receiving a START STOP UNIT command with the START bit equal to 1, the drive waits for a NOTIFY (ENABLE SPINUP) primitive. After receiving a NOTIFY (ENABLE S PINUP) primitive through either port, the drive becomes ready for normal operations within 20 seconds (excluding the error recovery procedure).
If the drive receives a START STOP UNIT command with the START bit and IMMED bit equal to 1 and does not receive a NOTIFY (ENABLE SPINUP) primitive within 5 seconds, the drive fails the START STOP UNIT command.
Cheetah 15K.5 SAS Product Manual, Rev. E
13
The START ST OP UN IT comm and m ay be used to comm and the dr ive to st op the spi ndle. Stop time is 30 sec­onds (maximum) from removal of DC power. There is no power control switch on the drive.

4.4 Prefetc h / m ulti-segmen te d ca ch e control

The drive provides a prefetch (read look-ahead) and multi-segmented cache control algorithms that in many cases can enhance system performance. Cache refers to the drive buffer storage space when it is used in cache operations. To select this feature, the host sends the Mode Select command with the proper values in the applicable bytes in page 08h. Prefetch and cache operations are independent features from the standpoint that each is enabled and disabled independently using the Mode Select command; however, in actual opera­tion, the prefetch feature overlaps cache operation somewhat as described in sections 4.5.1 and 4.5.2.
All default cache and prefetch mode parameter values (Mode Page 08h) for standard OEM versions of this drive family are given in Section 9.3.2.1.

4.5 Cache operation

Note. Refer to the SAS Interface Manual for more detail concerning the cache bits.
Of the 16 Mbytes physical buffer sp ace in the drive, approximately 13,000 kbytes can be used as a cache. The buffer is divided into logical segments from which data is read and to which data is written.
The drive keeps track of the logical block addresses of the data stored in each segment of the buffer. If the cache is enabled (see RCD bit in the SAS Interface Manual ), data requested by the host w ith a rea d comm and is retrieved from the buf fe r, if possible, before any disc access is initiated . If cach e oper ation is not en abled, the buffer is still used, but only as circular buffer segments during disc medium read operations (disregarding Prefetch operation for the moment). That is, the drive does not check in the buffer segments for the requested read data, but goes directly to the medium to retrieve i t. The retrieved data merely passes through some buf fer segment on the way to the host. All data transfers to the host are in accordance with buffer-full ratio rules. See the explanation provided with the information about Mode Page 02h (disconnect/reconnect control) in the SAS Interface Manual.
The following is a simplified description of the prefetch/cache operation: Case A—read command is received and all of the requested logical blocks are already in the cache:
1. Drive transfers the requested logical blocks to the initiator.
Case B—A Read command requests data, and at least one requested logical block is not in any segment of the cache:
1. The drive fetches the requested logical blocks from the disc and transfers them into a segment, and then
from there to the host in accordance with the Mode Select Disconnect/Reconnect parameters, page 02h.
2. If the prefetch feature is enabled, refer to section 4.5.2 for operation from this point.
Each cache segment is actually a self-contained circular buffer whose length is an integer number of logical blocks. The drive dynamically creates and removes segments based on the workload. The wrap-around capa­bility of the individual segments greatly enhances the cache’s overall performance.
Note. The size of each segment is not reported by Mode Sense command page 08h, bytes 14 and 15.
The value 0XFFFF is always reported regardless of the actual size of the segment. Sending a size specification using the Mode Select command (bytes 14 and 15) does not set up a new segment size. If the STRICT bit in Mode page 00h (byte 2, bit 1) is set to one, the drive responds as it does for any attempt to change an unchangeable parameter.
14
Cheetah 15K.5 SAS Product Manual, Rev. E

4.5.1 Caching write data

Write caching is a write operation by the drive that makes use of a drive buffer storage area where the data to be written to the medium is stored while the drive performs the Write command.
If read caching is enabled (RCD=0), then data written to the medium is retained in the cache to be made avail­able for future read cache hits. The same buffer space and segmentation is used as set up for read functions. The buffer segmentation scheme is set up or changed independently, having nothing to do with the state of RCD. When a write command is issued, if RCD=0, the cache is first checked to see if any logical blocks that are to be written are already stored in the cache from a previous read or write command. If there are, the respective cache segments are cleared. The new data is cached for subsequent Read commands.
If the number of write dat a logical blo cks excee d the size o f the segm ent b eing wr itten into, wh en th e en d of the segment is reached, the data is written i nto the b eginning of the same cache segment, overwriting the dat a that was written there at the beginning of the operation; however, the drive does not overwrite data that has not yet been written to the medium.
If write caching is enabled (WCE=1), then the drive may return Good status on a write command after the data has been transferred into the cache, but before the data has been written to the medium. If an error occurs while writing the data to the medium, and Good status has already been returned, a deferred error will be gen­erated.
The Synchronize Ca che command may be used to force the drive to write all cached wri te dat a to the med ium. Upon completion of a Synchronize Cache command, all data received from previous write commands will have been written to the medium.
Table 9.3.2.1 shows the mode default settings for the drive.

4.5.2 Prefetch operation

If the Prefetch feature is enabled, data in contiguous logical blocks on the disc immediately beyond that which was requested by a Read command are retrieved and stored in the buffer for immediate transfer from the buffer to the host on subsequent Read commands that request those logical blocks (this is true even if cache operation is disabled). Though the prefetch operation uses the buffer as a cache, finding the requested data in the buffer is a prefetch hit, not a cache operation hit.
To enable Prefetch, use Mode Select page 08h, byte 12, bit 5 (Disable Read Ahead - DRA bit). DRA bit = 0 enables prefetch.
The drive does not use the Max Prefetch field (bytes 8 and 9) or the Prefetch Ceiling field (bytes 10 and 11). When prefetch (read look-ahead) is enabled (enabled by DRA = 0), the drive enables prefetch of contiguous
blocks from the disc when it senses that a prefetch hit will likely occur. The drive disables prefetch when it decides that a prefetch hit is not likely to occur.
Cheetah 15K.5 SAS Product Manual, Rev. E
15

5.0 Reliability specifications

The following reliability specifications assume correct host and drive operational interface, including all inter­face timings, power supply voltages, environmental requirements and drive mounting constraints.
Seek error rate: Less than 10 errors in 108 seeks Read Error Rates
Recovered Data Less than 10 errors in 1012 bits transferred (OEM default settings) Unrecovered Data Less than 1 sector in 1016 bits transferred
Miscorrected Data Less than 1 sector in 1021 bits transferred Interface error rate: Less than 1 error in 1012 bits transferred MTBF 1,400,000 hours Preventive maintenance: None required
1. Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.

5.1 Error rate s

The error rates stated in this manual assume the following:
• The drive is operated per this specification using DC power as defined in this manual (see Section 6.2).
• Errors caused by host system failures are excluded from error rate computations.
• Assume random data.
• Default OEM error recovery settings are applied. This includes AWRE, ARRE, full read retries, full write retries and full retry time.
1

5.1.1 Recoverable Errors

Recoverable errors are those detected and corrected by the drive, and do not require user intervention. Recoverable Data errors will use correction, although ECC o n-the-fly is not considered fo r purposes o f recov-
ered error specifications. Recovered Data error rate is determined using read bits transferred for recoverable errors occurring during a
read, and using write bits transferred for recoverable errors occurring during a write.

5.1.2 Unrecoverable Errors

Unrecoverable Data Errors (Sense Key = 03h) are specified at less than 1 sector in error per 1016 bits trans­ferred. Unrecoverable Data Errors resulting from the same cause are treated as 1 error for that block.
16
Cheetah 15K.5 SAS Product Manual, Rev. E

5.1.3 Seek errors

A seek error is defined as a failure of the drive to position the heads to the addressed track. After detecting an initial seek error, the drive automaticall y perf orms an error recovery process. If the error recover y process fails, a seek positioning error (Error code = 15h or 02h) will be reported with a Hardware error (04h) in the Sense Key. Recoverable seek errors are specified at Less than 10 errors in 108 seeks. Unrecoverable seek errors (Sense Key = 04h) are classified as drive failures.

5.1.4 Interface errors

An interface error is defined as a failure of the receiver on a port to recover the data as transmitted by the device port connected to the receiver. The error may be detected as a running disparity error, illegal code, loss of word sync, or CRC error.

5.2 Reliability and service

You can enhance the reliability of Cheetah disc drives by ensuring that the drive receives adequate cooling. Section 6.0 provides temperature measurements and other information that may be used to enhance the ser­vice life of the drive. Section 8.2 provides recommended air-flow information.

5.2.1 Mean time between failure (MTBF)

The production disc drive shall achieve a MTBF of 1,400,000 hours when operated in an environment that ensures the HDA case temperatures specified in Section 6.4 are not exceeded. Short-term excursions up to the specification limits of the operating environment will not affect MTBF performance. Continual or sustained operation at case temperatures above the values shown in Section 6.4.1 may degrade product reliability.
The MTBF target is specified as device power-on hours (POH) for all drives in service per failure.
MTBF = Estimate power-on operating hours in the period
----------------------------------------------------------------­Number of drive failures in the period
Estimated power-on operation hours means power-up hours per disc drive times the total number of disc drives in service. Each disc drive shall have accumulated at least nine months of operation. Data shall be cal­culated on a rolling average base for a minimum period of six months.
MTBF is based on the following assumptions:
• 8,760 power-on hours per year.
• 250 average on/off cycles per year.
• Operations at nominal voltages.
• Systems will provide adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not exceeded.
Drive failure means any stoppage or substandard performance caused by drive malfunction. A S.M.A.R.T. predictive failure indicates that the drive is deteriorating to an imminent failure and is considered
an MTBF hit.

5.2.2 Preventive mainte nan ce

No routine scheduled preventive maintenance is required.
Cheetah 15K.5 SAS Product Manual, Rev. E
17

5.2.3 Hot plugging the drive

When a disc is powered on by switching the power or hot plugged, the drive runs a self test before attempting to communicate on its’ interfaces. When the self test completes successfully, the drive initiates a Link Reset starting with OOB. An attached device should respond to the link reset. If the link reset attempt fails, or any time the drive looses sync, the drive initiated link reset. The drive will initiate link reset once per second but alternates between port A and B. Therefore each port will attempt a link reset once per 2 seconds assuming both ports are out of sync..
If the self-test fails, the does not respond to link reset on the failing port. Note. It is the responsibility of the systems integrator to assure that no temperature, energy, voltage haz-
ard, or ESD potential hazard is presented during the hot connect/disconnect operation. Discharge the static electricity from the drive carrier prior to inserting it into the system.
Caution. The drive motor m ust come to a com pl ete s top pr ior to ch angi ng the pla ne of o pera ti on. T his time i s
required to insure data integrity.

5.2.4 S.M.A.R.T.

S.M.A.R.T. is an acronym for Self-Monitoring Analysis and Reporting Technology. This technology is intended to recognize conditions that indicate imminent drive failure and is designed to provide sufficient warning of a failure to allow you to back up the data before an actual failure occurs.
Note. The drive’ s f irmwar e m onitor s speci fic attr ibutes for degradation ove r tim e b ut can ’ t pr edict in sta nt a-
neous drive failures.
Each monitored attribute has been selected to monitor a specific set of failure conditions in the operating per­formance of the drive and the thresholds are optimized to minimize “false” and “failed” predi ctions.
Controlling S.M.A.R.T.
The operating mode of S.M.A.R. T. is controlled by the DEXCPT and PERF bits on the Informational Exce ptions Control mode page (1Ch). Use the DEXCPT bit to enable or disable the S.M.A.R.T. feature. Setting the DEX­CPT bit disables all S.M.A.R.T. functions. When enab led, S .M. A.R.T. collects on -line d ata as the drive p erfor ms normal read and write operations. When the PERF bit is set, the drive is considered to be in “On-line Mode Only” and will not perform off-line functions.
You can measure off-line attributes and force the drive to save the data by using the Rezero Unit command. Forcing S.M.A.R.T. resets the timer so that the next scheduled interrupt is in two hours.
You can interrogate the drive through th e host t o dete rmine the time remaining b efore the ne xt schedu l ed me a­surement and d at a logg i ng p rocess occur s . To accomplish this, i ssue a Log Sense command to log page 0x3E. This allows you to control when S.M.A.R.T. interruptions occur. Forcing S.M.A.R.T. with the RTZ command resets the timer.
Performance impact
S.M.A.R.T. attribute data is saved to the disc so that the events that caused a predictive failure can be recre­ated. The drive measures and saves parameters once every two hours subject to an idle period on the drive interfaces. The process of measuring off-line attribute data and saving data to the disc is uninterruptable. The maximum on-line only processing delay is summarized below:
Maximum processing delay
S.M.A.R.T. delay times
On-line only delay DEXCPT = 0, PERF = 1
42 milliseconds
Fully-enabled delay DEXCP T = 0, PE R F = 0
163 milliseconds
18
Cheetah 15K.5 SAS Product Manual, Rev. E
Reporting control
Reporting is controlled by the MRIE bits in the Informational Exceptions Control mode page (1Ch). Subject to the reporting method, the firmware will issue to the host an 01-5Dxx sense code. The error code is preserved through bus resets and power cycles.
Determining rate
S.M.A.R.T. monitors the rate at which errors occur and si gna ls a predi ctive fai lure if the rat e of degrad ed err ors increases to an unacceptabl e level. To determine rate, error events are logged and com pa red to the num ber of total operations for a given attribute. The interval defines the number of operations over which to measure the rate. The counter that keeps track of the current number of operations is referred to as the Interval Counter.
S.M.A.R.T. measures error rates. All errors for each monitored attribute are recorded. A counter keeps track of the number of errors for the current interval. This counter is referred to as the Failure Counter.
Error rate is the number of errors per oper ation. The algori thm tha t S .M.A.R .T. uses to record rate s of err or i s to set thresholds for the number of errors and their interval. If the number of errors exceeds the threshold before the interval expires, the error rate is considered to be unacceptable. If the number of errors does not exceed the threshold before the interval expires, the error rate is considered to be acceptable. In either case, the inter­val and failure counters are reset and the process starts over.
Predictive failures
S.M.A.R.T. signals predictive failures when the drive is performing unacceptably for a period of time. The firm­ware keeps a running count of the number of times the error rate for each attribute is unacceptable. To accom­plish this, a counter is incremented each time the error rate is unacceptable and decremented (not to exceed zero) whenever the error rate is acceptable. If the counter continually increments such that it reaches the pre­dictive threshold, a predictive failure is signaled. This counter is referred to as the Failure History Counter. There is a separate Failure History Counter for each attribute.

5.2.5 Thermal monitor

Cheetah drives implement a temperature warning system which:
1. Signals the host if the temperature exceeds a value which would threaten the drive.
2. Signals the host if the temperature exceeds a user-specified value.
3. Saves a S.M.A.R.T. data frame on the drive which exceeds the threatening temperature value.
A temperature sensor monitors the drive temperature and issues a warning over the interface when the tem­perature exceeds a set threshold. The temperature is measured at power-up and then at ten-minute intervals after power-up.
The thermal monitor system generates a warning code of 01-0B01 when the temperature exceeds the speci­fied limit in compliance with the SCSI standard. The drive temperature is reported in the FRU code field of mode sense dat a. You can use this infor matio n to deter mine if the warning i s due to t he tem per atur e excee ding the drive threatening temperature or the user-specified temperature.
This feature is controlled by the En able W a rni ng (EWasc) bit, and the reporting mechanism is controlled by the Method of Reporting Informational Exceptions field (MRIE) on the Informational Exceptions Control (IEC) mode page (1Ch).
The current algorithm implements two temperature trip points. The first trip point is set at 68°C which is the maximum temperature limit according to the drive specification. The second trip point is user-selectable using the Log Select command. The re feren ce tempe ratur e p aram eter in the tempera ture log page (see Table 1) can
Cheetah 15K.5 SAS Product Manual, Rev. E
19
be used to set this trip point. The default value for this drive is 68°C, however, you can set it to any value in the range of 0 to 68°C. If you specify a temperature greater than 68°C in this field, the temperature is rounded down to 68°C. A sense code is sent to the host to indicate the rounding of the parameter field.
Table 1: Temperature Log Page (0Dh)
Parameter Code Description
0000h 0001h
Primary Temperature Reference Temperature

5.2.6 Drive Self Test (DST)

Drive Self Test (DST) is a technology designed to recognize drive fault conditions that qualify the drive as a failed unit. DST validates the functionality of the drive at a system level.
There are two test coverage options implemented in DST:
1. Extended test
2. Short text The most thorough option is the extended test that performs various tests on the drive and scans every logical
block address (LBA) of the drive. The short test is time-restricted and limited in length—it does not scan the entire media surface, but does some fundamental tests and scans portions of the media.
If DST encounters an error during either of these tests, it reports a fault condition. If the drive fails the test, remove it from service and return it to Seagate for service.
5.2.6.1 DST failure definition
The drive will present a “diagnostic failed” condition through the self-tests results value of the diagnostic log page if a functional failure is encountered during DST. The channel and servo parameters are not modified to test the drive more stringently, and the number of retries are not reduced. All retries and recovery processes are enabled during the test. If data is recoverable, no fa ilure condition will be reported regardless of the number of retries required to recover the data.
The following conditions are considered DST failure conditions:
• Seek error after retries are exhausted
• Track-follow error after retries are exhausted
• Read error after retries are exhausted
• Write error after retries are exhausted Recovered errors will not be reported as diagnostic failures.
5.2.6.2 Implementation
This section provides all of the information necessary to implement the DST function on this drive.
20
Cheetah 15K.5 SAS Product Manual, Rev. E
5.2.6.2.1 State of the drive prior to testing
The drive must be in a ready state before issuing the Send Diagnostic command. There are multiple reasons why a drive may not be ready, some of which are valid conditio ns, and not erro rs. For example, a drive may be in process of doing a form at, or anothe r D ST. It is the responsibility o f the ho st applic atio n to det erm ine the “ not ready” cause.
While not technically part of DST, a Not Ready condition also qualifies the drive to be returned to Seagate as a failed drive.
A Drive Not Ready condition is reported by the drive under the following conditions:
• Motor will not spin
• Motor will not lock to speed
• Servo will not lock on track
• Drive cannot read configuration tables from the disc
In these conditions, the drive responds to a Test Unit Ready command with an 02/04/00 or 02/04/03 code.
5.2.6.2.2 Invoking DST
To invoke DST, submit the Send Diagnostic command with the appropriate Function Code (001b for the short test or 010b for the extended test) in bytes 1, bits 5, 6, and 7.
5.2.6.2.3 Short and extended tests
DST has two testing options:
1. short
2. extended
These testing options are described in the following two subsections. Each test consists of three segments: an electrical test segment, a servo test segment, and a read/verify scan
segment.
Short test (Function Code: 001b)
The purpose of the short test is to provide a time-limited test that tests as much of the drive as possible within 120 seconds. The short test does not scan the entire media surface, but does some fundamental tests and scans portions of the media. A complete rea d/ver ify scan is not per formed and onl y factu al failu res will report a fault condition. This option provides a quick confidence test of the drive.
Extended test (Function Code: 010b)
The objective of the extended test option is to empirically test critical drive components. For example, the seek tests and on-track operations test the positioning mechanism. The read operation tests the read head element and the media surface. The write element is tested through read/write/read operations. The integrity of the media is checked through a read/verify scan of the media. Motor functionality is tested by default as a part of these tests.
The anticipated length of the Extended test is reported through the Control Mode page.
5.2.6.2.4 Log page entries
When the drive begins DST, it creates a new entry in the Self-test Results Log page. The new entry is created by inserting a new self-te st parameter block a t the beginning of t he se lf-test results log p a ram eter section of the log page. Existing data will be moved to make room for the new parameter block. The drive reports 20 param­eter blocks in the log p ag e. If th ere are more than 20 p ar amet er blocks, the least r ecent p a rame ter block will be deleted. The new parameter block will be initialized as follows:
1. The Function Code field is set to the same value as sent in the DST command
Loading...
+ 60 hidden pages