Table 5: Read and write retry count maximum recovery times [1]

Read retry

Maximum recovery time per LBA

count

(cumulative, msec)

 

 

0

51.87

 

 

1

59.85

 

 

2

203.49

 

 

3

219.45

 

 

4

253.11

 

 

5

279.35

 

 

6

311.27

 

 

7

395.12

 

 

8

463.12

 

 

9

495.04

 

 

10

530.95

 

 

11 (default)

1,282.97

 

 

[1]These values are subject to change.

Write retry

Maximum recovery time per LBA

count

(cumulative, msec)

 

 

0

23.94

 

 

1

35.91

 

 

2

55.86

 

 

3

67.83

 

 

4

119.79

 

 

5 (default)

147.72

 

 

Setting these retry counts to a value below the default setting could result in an increased unrecovered error rate which may exceed the value given in this product manual. A setting of zero (0) will result in the drive not performing error recovery.

For example, suppose the Read/Write Recovery page has the RC bit set to 0, read retry count set to 4, and the recovery time limit field (Mode Sense page 01, bytes 10 and 11) set to FF FF hex (maximum). A four LBA Read command is allowed to take up to 253.11 msec recovery time for each of the four LBAs in the command. If the recovery time limit is set to 00 C8 hex (200 msec decimal) a four LBA read command is allowed to take up to 200 msec for all error recovery within that command. The use of the Recovery Time Limit field allows finer granularity on control of the time spent in error recovery. The recovery time limit only starts counting when the drive is executing error recovery and it restarts on each command. Therefore, each command’s total recovery time is subject to the recovery time limit. Note: A recovery time limit of 0 will use the drive’s default value of FF FF. Minimum recovery time limit is achieved by setting the Recovery Time Limit field to 00 01.

7.3FC-AL system errors

Information on the reporting of operational errors or faults across the interface is given in the Fibre Channel Interface Manual. The FCP Response returns information to the host about numerous kinds of errors or faults. The Receive Diagnostic Results reports the results of diagnostic operations performed by the drive.

Status returned by the drive to the initiator is described in the Fibre Channel Interface Manual. Status reporting plays a role in systems error management and its use in that respect is described in sections where the various commands are discussed.

7.4Background Media Scan

Background Media Scan (BMS) is a self-initiated media scan. BMS is defined in the T10 document SPC-4 available from the T10 committee. BMS performs sequential reads across the entire pack of the media while the drive is idle. In RAID arrays, BMS allows hot spare drives to be scanned for defects prior to being put into service by the host system. On regular duty drives, if the host system makes use of the BMS Log Page, it can avoid placing data in suspect locations on the media. Unreadable and recovered error sites will be logged or reallocated per ARRE/AWRE settings.

Cheetah 15K.5 FC Product Manual, Rev. D

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Seagate ST3146855FC, ST3300655FC, ST373455FC manual FC-AL system errors, Background Media Scan
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ST3146855FC, ST373455FC, ST3300655FC specifications

Seagate is renowned for its commitment to high-performance data storage solutions, and their range of enterprise drives, including the ST3300655FC, ST373455FC, and ST3146855FC, demonstrates this dedication. These models cater to businesses requiring robust, reliable, and efficient hard disk drives (HDDs) designed for demanding environments.

The ST3300655FC offers a capacity of 300 GB, making it suitable for a variety of enterprise applications. It utilizes a 15,000 RPM spindle speed, which significantly enhances its performance, delivering quick read and write times. This drive supports Serial Attached SCSI (SAS) interface, ensuring faster data transfer rates and reliability essential for critical computing environments. The dual-port connectivity of SAS allows for enhanced fault tolerance and redundancy, making the ST3300655FC ideal for data centers and enterprise storage systems.

Following closely, the ST373455FC provides a slightly larger capacity of 734 GB while maintaining the same 15,000 RPM speed. This drive's design focuses on high availability, making it an excellent choice for applications that require continuous uptime. Like its counterpart, it also benefits from the SAS interface, ensuring that data can be accessed quickly and reliably. The robust construction of the ST373455FC guarantees consistent performance under heavy workloads, an essential characteristic for enterprise use.

The ST3146855FC, with a capacity of 146 GB, offers a balance between speed and storage for enterprises that do not require the larger capacities provided by the other two models. It also operates at 15,000 RPM, benefiting from similar technological advancements as the ST3300655FC and ST373455FC. This drive maintains compatibility with existing systems, making it a versatile option for organizations looking to upgrade their storage solutions without overhauling their infrastructure.

All three models exhibit Seagate's commitment to durability and low power consumption, which is critical for reducing operational costs in data centers. They also feature advanced error recovery and data integrity technologies, ensuring that critical data remains intact and accessible. Enhanced thermal and vibration tolerance further extends the lifespan of these drives in challenging environments.

In summary, the Seagate ST3300655FC, ST373455FC, and ST3146855FC are tailored to meet the rigorous demands of enterprise environments. Their high spindle speeds, SAS connectivity, and robust designs make them exemplary choices for businesses seeking reliable and efficient storage solutions. Their distinctive features and technologies ensure that they deliver outstanding performance, data integrity, and durability, making them invaluable assets in any data-driven organization.
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