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 "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 cell as the defective sector's and is effective until all spare sectors in that cell are used up.

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

3-10

C141-E205

Page 44
Image 44
Fujitsu MAU3036NC/NP, MAU3073NC/NP, MAU3147NC/NP manual Defect Management Defect list, Alternate block allocation

MAU3036NC/NP, MAU3147NC/NP, MAU3073NC/NP specifications

The Fujitsu MAU3036NC/NP, MAU3147NC/NP, and MAU3073NC/NP are advanced models designed to offer high performance and reliability in various computing environments. These models are particularly notable for their optimized efficiency and robust feature set, making them suitable for a range of applications from enterprise servers to high-performance computing.

One of the standout features of the MAU series is its reliance on cutting-edge technology that maximizes data handling capabilities. The MAU3036NC/NP boasts a formidable capacity for high-speed data processing, making it ideal for tasks requiring quick data retrieval and storage. With an optimized caching mechanism, this model enhances data throughput and reduces latency, contributing to an overall faster response time in demanding applications.

The MAU3147NC/NP introduces further advancements with its enhanced thermal management system. This ensures that the unit operates at optimal temperatures, reducing the risk of overheating and prolonging the lifespan of the hardware. Additionally, this model implements advanced error-correcting code (ECC) memory, which significantly improves reliability by detecting and correcting internal data corruption, a crucial feature in mission-critical environments.

Meanwhile, the MAU3073NC/NP excels in terms of scalability. Its architecture allows for easy upgrades and expansions, accommodating growing data needs without significant downtime. This flexibility is essential for businesses looking to future-proof their operations and adapt to changing demands seamlessly.

All three models incorporate Fujitsu's innovative energy-efficient technologies, which not only reduce power consumption but also align with global sustainability goals. The intelligent power management systems make these units not only cost-effective but also environmentally friendly, demonstrating Fujitsu's commitment to responsible manufacturing.

Furthermore, robust connectivity options, including multiple interface support, make these models easily integrable into existing IT infrastructures. They are compatible with a variety of operating systems and software, ensuring that users can leverage their full potential regardless of their specific setup.

In summary, the Fujitsu MAU3036NC/NP, MAU3147NC/NP, and MAU3073NC/NP series exemplify the blend of performance, reliability, and efficiency. With features tailored to meet the evolving needs of modern businesses, these models stand out in the competitive landscape of computing solutions, ensuring that users can address both current and future challenges in data management and processing.