3.3Defect Management

3.3.1Defect list

Information of the defect location on the disk is managed by the defect list. The following are defect lists which the IDD manages.

∙P list (Primary defect list): This list consists of defect location information available at the disk drive shipment and is recorded in a system space. The defects in this list are permanent, so the INIT must execute the alternate block allocation using this list when initializing the disk.

∙D list (Data defect list): This list consists of defect location information specified in a FORMAT UNIT command by the INIT at the initialization of the disk. This information is recorded in the system space of the disk drive as the G list. To execute the alternate block allocation, the FORMAT UNIT command must be specified.

∙G list (Growth defect list): This list consists of defective logical data block location information specified in a REASSIGN BLOCKS command by the INIT, information on defective logical data blocks assigned alternate blocks by means of IDD automatic alternate block allocation, information specified as the D list, and information generated as the C list. They are recorded in the system space on the disk drive.

The INIT can read out the contents of the P and G lists by the READ DEFECT DATA command.

3.3.2Alternate block allocation

The alternate data block is allocated to a defective data block (= sectors) in defective sector units by means of the defect management method inside the IDD.

The INIT can access all logical data blocks in the user space, as long as there is no error.

Spare sectors to which alternate blocks are allocated can be provided in either "spare sectors in a cylinder" or "alternate cylinders". See Subsection 3.1.2 for details.

The INIT can specify the size and area for spare sectors by the MODE SELECT command at the time of the initialization of the disk.

Both of the following are applicable to the alternate block allocation.

∙Sector slip treatment: Defective sectors are skipped and the logical data block corresponding to those sectors is allocated to the next physical sectors. This treatment is made on the same cylinder as the defective sector's and is effective until all spare sectors in that cylinder are used up.

∙Alternate sector treatment: The logical data block corresponding to defective sectors is allocated to unused spare sectors in the same cylinder or unused spare sectors in the alternate cylinder.

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Fujitsu MAE3091LC, MAF3364LP, MAF3364LC, MAG3182LC, MAE3182LC manual Defect Management Defect list, Alternate block allocation
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MAE3091LC, MAE3182LC, MAG3182LC, MAF3364LC, MAF3364LP specifications

The Fujitsu MAF3364LC, MAE3091LC, MAF3364LP, MAG3182LC, and MAE3182LC are distinguished members of Fujitsu's hard drive lineup, tailored for high-performance computing and storage solutions. Each of these drives possesses unique features and technologies, making them suitable for various applications in computing environments.

The MAF3364LC is a high-capacity and high-performance SCSI hard disk drive that offers a storage capacity of up to 6.4 GB. It operates at a spindle speed of 10,000 RPM, ensuring fast data access and transfer rates. This drive utilizes advanced technology designs, such as a fluid dynamic bearing spindle motor, which enhances reliability and reduces noise levels. Its SCSI interface allows for multiple device connections, making it ideal for enterprise-level applications where performance is critical.

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The MAG3182LC is known for its high-capacity support and performance balance, with 18.2 GB of storage and a spindle speed of 10,000 RPM. It boasts enhanced data integrity features and advanced error correction technologies that allow for high data accuracy and reliability, ensuring that enterprises can depend on their stored information.

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