9.0DEFECT AND ERROR MANAGEMENT

Seagate continues to use innovative technologies to manage defects and errors. These technologies are designed to increase data integrity, perform drive self-maintenance, and validate proper drive operation.

SCSI defect and error management involves drive internal defect/error management and SAS system error considerations (errors in communications between the initiator and the drive). In addition, Seagate provides the following technologies used to increase data integrity and drive reliability:

•Background Media Scan (see Section 9.4)

•Auto-Reallocation (see Section 9.5)

The read error rates and specified storage capacities are not dependent on host (initiator) defect management routines.

9.1DRIVE INTERNAL DEFECTS/ERRORS

During the initial drive manufacturing test operation at the factory, media defects are identified, tagged as being unusable, and their locations recorded on the drive primary defects list (referred to as the “P’ list). At factory format time, these known defects are also deallocated, that is, marked as retired and the location listed in the defects reallocation table. The “P” list is not altered after factory formatting. Locations of defects found and reallocated during error recovery procedures after drive shipment are listed in the “G” list (defects growth list). The “P” and “G” lists may be referenced by the initiator using the READ DEFECT DATA command.

Details of the SCSI commands supported by the drive are described in the SAS Interface Manual. Also, more information on the drive Error Recovery philosophy is presented in the SAS Interface Manual.

The drive uses a vendor unique format to report defects via the READ DEFECT DATA command pending T10 standardization of a format for Solid State Devices. This format defect type is defined as 110b in the SCSI FORMAT UNIT command. The definition of the 110b format is defined in the following table.

Table 13 SSD Physical format address descriptor

Byte

Bit

7

6

5

 

4

 

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

(MSB)

 

 

 

MEDIA ID

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

 

 

 

 

 

 

 

 

 

(LSB)

 

 

 

 

 

 

 

 

 

 

2

 

 

 

 

 

CHANNEL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3

 

 

 

 

 

 

DIE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

 

(MSB)

 

 

 

 

BLOCK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

 

 

 

 

 

 

 

 

 

 

(LSB)

 

 

 

 

 

 

 

 

 

 

6

 

 

 

 

 

RESERVED

 

 

 

 

 

 

 

 

 

 

 

 

7

 

 

 

 

VENDOR UNIQUE

 

 

 

The MEDIA ID field contains an identifier for the flash controller for devices that utilize more than one flash controller. The CHANNEL field contains the channel number within the corresponding Flash Controller.

The DIE field contains the die number within channel. The BLOCK field contains the block number within the die.

The VENDOR UNIQUE field may contain vendor unique information.

PULSAR.2 SAS PRODUCT MANUAL, REV. C

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Seagate ST800FM0032, ST100FM0012, ST100FM0052 manual Defect and Error Management, SSD Physical format address descriptor
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ST800FM0002, ST100FM0002, ST200FM0002, ST400FM0012, ST800FM0032 specifications

The Seagate ST100FM0012, ST800FM0012, ST400FM0042, ST400FM0002, and ST100FM0052 are high-performance hard drives designed for enterprise applications, offering advanced features and reliability for demanding workloads.

The ST100FM0012 is a 10TB hard drive that strikes a balance between capacity and performance. It utilizes a 7200 RPM spindle speed and features a 256MB cache, enabling efficient data access and enhanced read/write performance. With Seagate’s AgileArray technology, the ST100FM0012 is optimized for NAS environments, providing multi-drive reliability and error recovery.

The ST800FM0012 is an 8TB variant that shares many features with its 10TB counterpart but is tailored for organizations needing robust storage without reaching the highest tier of capacity. Its dual-plane rotational vibration technology minimizes vibration in multi-drive systems, ensuring sustained performance over prolonged use. This makes it an excellent choice for virtualization and data-intensive applications.

The ST400FM0042 offers a 4TB capacity suited for smaller enterprise needs or as a backup solution. With an impressive performance profile, including a 7200 RPM speed and 128MB cache, it accommodates both sequential and random workloads with ease. This drive stands out with its PowerChoice technology, allowing users to manage power consumption and reduce operational costs.

Another 4TB option, the ST400FM0002, is particularly designed for hybrid configurations, pairing the fast access of the hard drive with the speed of SSDs. It features Seagate's advanced thermal management technologies, ensuring optimal operating temperatures and performance stability during intensive workloads.

The ST100FM0052 rounds out the lineup with a 10TB capacity but is specifically aimed at surveillance applications. It supports a workload rate of 180TB per year, making it ideal for always-on recording scenarios. The drive is built with optimized firmware, which ensures enhanced performance in write-intensive environments, essential for video recording and security systems.

All these drives are equipped with Seagate’s proprietary technologies, including data recovery services and built-in data protection features, ensuring data integrity and security. The drives are built for durability, reliability, and high performance in mission-critical environments, making them indispensable components of modern enterprise data storage solutions. With capacities ranging from 4TB to 10TB, they cater to varying storage needs across different sectors.
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