Data Format

3.1.5Format capacity

The size of the usable area for storing user data on the HDD (format capacity) varies according to the logical data block or the size of the spare sector area. Table 3.1 lists examples of the format capacity when the typical logical data block length and the default spare area are used. The following is the general formula to calculate the format capacity.

[Number of sectors of each zone] = [number of sectors per track ⋅ number of tracks per cell – number of alternate spare sectors per cell] ⋅ [number of cells in the zone]

[Formatted capacity] = [total of sectors of all zones] ⎟ [number of physical sectors in logical block] ⋅ [logical data block length]

The following formula must be used when the number of logical data blocks are specified with the parameter in the MODE SELECT or MODE SELECT EXTENDED command.

[Format capacity] = [logical data block length] ⋅ [number of logical data blocks]

The logical data block length, the maximum logical block address, and the number of the logical data blocks can be read out by a READ CAPACITY, MODE SENSE, or MODE SENSE EXTENDED command after initializing the disk medium.

 

Table 3.1

Format capacity

 

 

 

 

 

 

Model

Data block length

 

User blocks

Format capacity (GB)

 

 

 

 

 

MAW3300FC

 

 

585,937,500

300.0 (*)

 

512

 

 

 

MAW3147FC

 

287,277,984

147.0 (*)

 

 

 

 

 

MAW3073FC

 

 

143,638,992

73.5 (*)

 

 

 

 

 

(*) 1GB=1,000,000,000 bytes

Note:

Total number of spare sectors is calculated by adding the number of spare sectors in each primary cylinder and the number of sectors in the alternate cylinders.

3.2Logical Data Block Addressing

Independently of the physical structure of the disk drive, the HDD adopts the logical data block addressing as a data access method on the disk medium. The HDD relates a logical data block address to each physical sector at formatting. Data on the disk medium is accessed in logical data block units. The initiator specifies the data to be accessed using the logical data block address of that data.

The logical data block addressing is a function whereby individual data blocks are given addresses of serial hexadecimal numbers in each drive.

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Fujitsu MAW3147FC, MAW3300FC, MAW3073fc manual Format capacity

MAW3073fc, MAW3147FC, MAW3300FC specifications

The Fujitsu MAW3073fc, MAW3300FC, and MAW3147FC are high-performance Fibre Channel hard disk drives that cater to enterprise storage solutions. Designed for demanding applications, these drives are engineered to deliver reliability, speed, and capacity, making them suitable for data centers and other high-availability environments.

The MAW3073fc offers a storage capacity of 73GB and operates at 15,000 RPM, ensuring rapid data access and high throughput. This drive features advanced error correction capabilities, enhancing data integrity while minimizing downtime. The MAW3073fc supports the Fibre Channel interface, enabling fast data transfer rates that are essential for high-performance computing scenarios.

Following this, the MAW3300FC steps up the game with a larger capacity of 300GB, also spinning at 15,000 RPM. It boasts enhanced reliability features, including improved thermal management and vibration tolerance, which significantly reduce wear and tear and prolong the drives' lifespan. Its hot-swappable design allows for easy maintenance, making it an ideal choice for critical applications that require minimal disruptions.

The MAW3147FC further expands the offering with a storage capacity of 147GB. Designed for applications that require a balance between performance and capacity, this drive provides a reliable solution for enterprise environments. Like its counterparts, it operates at 15,000 RPM, ensuring swift data retrieval and consistency under heavy loads. The MAW3147FC also implements sophisticated caching algorithms that optimize read and write performance.

All three drives utilize SCSI command sets and feature RAID support, making them compatible with various enterprise storage systems. These drives are built with enterprise-grade components, ensuring durability and reliability, crucial in mission-critical setups. The combination of high RPM speeds, reliability features, and large capacities makes the Fujitsu MAW series an excellent choice for organizations looking to enhance their storage infrastructure.

In terms of technologies, these drives use advanced servo technology and tight mechanical tolerances to achieve high precision and performance. Moreover, they are designed to operate in environments with rigorous temperature and humidity controls, further enhancing their reliability. The MAW series exemplifies Fujitsu's commitment to providing high-quality, performance-driven storage solutions for modern enterprise needs.