6.2 Disk Media Initialization

Alternate block allocation processing during FORMAT UNIT command execution

With the FORMAT UNIT command, alternate block allocation is done by sector slip processing until all the spare sectors within the same cell have been used up for defective sectors included in the type of defect list (P, G or D) specified in the command. When all the spare sectors in the same cell have been used up, subsequent defective sectors in that cell are treated by allocating spare sectors in an alternate cell by alternate sector processing.

After implementing this alternate block allocation and initializing the disk media, at times when a data block Verify (Certification) operation is not prohibited, the IDD, reads all the initialized data blocks and verifies their normalcy. If a defective data block is detected during this processing, the IDD generates the C List as defect position information and allocates alternate blocks by alternate sector processing for those defective data blocks. In this case, if there are any unused spare sectors in the same cell as the defective data blocks, alternate blocks are allocated within the same cell, but if the spare sectors are all used up in the same cell, alternate blocks are allocated in spare sectors in an alternate cell.

Alternate block allocation processing by the REASSIGN BLOCKS command

With the REASSIGN BLOCKS command, alternate block allocation is performed by alternate sector processing for defective logical data blocks specified by the INIT. In this case, if there are unused spare sectors in the same cell as the specified defective logical data blocks, alternate block allocation is done within the same cell, but if all the spare sectors in the same cell have been used up, alternate blocks are allocated in spare sectors in an alternate cell.

Auto alternate block allocation processing

If auto alternate block allocation processing is permitted by the AWRE flag or the ARRE flag of the MODE SELECT parameters, the IDD executes alternate clock allocation automatically by alternate sector processing for defective data blocks detected during execution of the WRITE, WRITE EXTENDED, WRITE AND VERIFY, READ and READ EXTENDED commands. The alternate block allocation method in this case is the same as in the case of the REASSIGN BLOCKS command. See the description in Section 5.3.2 concerning "Auto Alternate Block Allocation Processing".

6.2Disk Media Initialization

6.2.1Initialization during installation

The disk drive is initialized for the inherent (default) data format for each respective model name (model class) when it is shipped from the factory, so ordinarily, it is not necessary to initialized (format) the disk media when it is installed in a system. However, in cases where data attributes which differ from the default format are necessary, initialization (formatting) of the entire disk media by the following procedures is necessary. At this time, the INIT can change the following data format attributes.

The logical data block length.

The number of logical data blocks or the number of cylinders in the User Space.

The size of the spare area for alternate blocks.

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Fujitsu MAP3735, MAP3367, MAP3147, MAS3735, MAS3367 Disk Media Initialization Initialization during installation

MAP3735, MAP3147, MAS3367, MAP3367, MAS3735 specifications

Fujitsu, a renowned leader in technology and innovation, has developed a variety of reliable hard disk drives (HDDs) that cater to a wide range of data storage needs. Among these, the MAS3735, MAP3367, MAS3367, MAP3147, and MAP3735 series stand out for their advanced features and exceptional performance.

The MAS3735 is a high-capacity enterprise-class drive that boasts a storage capacity of up to 300 GB. Its 10,000 RPM spindle speed ensures rapid data retrieval and efficient performance, making it ideal for data-intensive applications. It utilizes a Serial Attach SCSI (SAS) interface, which allows for improved data transfer rates and increased reliability compared to traditional SATA drives. The drive is designed with advanced technologies such as error recovery and data integrity features, ensuring the safety and security of critical data.

Similarly, the MAP3367 and MAS3367 models are geared towards both enterprise and mid-range server environments, providing a storage capacity of up to 300 GB as well. These drives also operate at a spindle speed of 15,000 RPM, offering swift access times that enhance overall system performance. The MAP3367 employs the Ultra 320 SCSI interface, allowing for significant bandwidth and ensuring data is transmitted efficiently.

On the other hand, both MAP3147 and MAP3735 models provide versatile solutions for various applications, supporting capacities from 36 GB to 147 GB. The MAP3147, with its 10,000 RPM speed, is optimized for workloads requiring quick access and high throughput, making it suitable for transactional systems and enterprise applications. The MAP3735, while offering comparable capacity, emphasizes exceptional reliability and durability, which is crucial for environments that involve heavy data loads.

All these Fujitsu HDDs are characterized by their robust construction, reliability, and efficiency. They are built to withstand heavy workloads and are equipped with features like advanced thermal management and acoustic noise reduction, ensuring they operate effectively in data center environments.

In conclusion, Fujitsu's MAS3735, MAP3367, MAS3367, MAP3147, and MAP3735 series HDDs are designed for high performance and reliability, catering to both enterprise and mid-range environments. Their advanced features make them a strong choice for businesses looking to enhance their storage solutions while maintaining data integrity and system performance.