3.1.5Format capacity

The size of the usable area for storing user data on the IDD (format capacity) varies according to the logical data block or the size of the spare sector area. Table 3.4 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 3.4 Format capacity

Model

Data heads

Data block length

User blocks

Format capacity (GB)

 

 

 

 

 

MAP3147NC/NP

8

 

287,132,440

147.01

 

 

 

 

 

MAP3735NC/NP

4

512

143,571,316

73.50

 

 

 

 

 

MAP3367NC/NP

2

 

71,775,284

36.74

 

 

 

 

 

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 IDD adopts the logical data block addressing as a data access method on the disk medium. The IDD 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 INIT 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 binaries in each drive.

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Fujitsu MAP3147NC/NP, MAP3735NC/NP, MAP3367NC/NP manual Format capacity
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MAP3735NC/NP, MAP3367NC/NP, MAP3147NC/NP specifications

Fujitsu's MAP3147NC/NP, MAP3367NC/NP, and MAP3735NC/NP hard disk drives represent a robust solution for businesses seeking reliable data storage options. These models are part of Fujitsu’s extensive line of high-performance hard drives that cater to various organizational needs, from servers to high-capacity data storage systems.

One of the standout features of these hard drives is their speed. The MAP3147NC/NP operates at a spindle speed of 10,000 RPM, ensuring rapid data access and retrieval. This speed is essential for environments requiring quick data transactions, making it suitable for enterprise-level databases and high-performance computing applications.

The capacity range across these models is designed to meet varying storage requirements. The MAP3147NC offers 147 GB, while the MAP3367NC provides 67 GB, and the MAP3735NC boasts a generous capacity of 35 GB. This diversity allows organizations to select the drive that best fits their data storage and performance needs while maintaining a scalable storage solution.

In terms of technology, the drives incorporate advanced features such as Serial Attached SCSI (SAS) interface, which enhances data throughput and reliability compared to traditional Parallel SCSI interfaces. SAS technology enables these drives to support multiple device connections while ensuring high-performance throughput, essential for modern enterprise environments.

The drives employ a 64 MB cache, providing a significant performance boost by allowing for quicker access to frequently used data. This capability improves overall system responsiveness, especially in applications requiring high input/output operations per second (IOPS).

Moreover, the MAP3147NC/NP, MAP3367NC/NP, and MAP3735NC/NP series are designed with data integrity in mind. They include features such as Error Correction Code (ECC) and background error scanning, which work together to maintain the integrity of stored data and minimize the risk of data loss.

In conclusion, Fujitsu’s MAP3147NC/NP, MAP3367NC/NP, and MAP3735NC/NP hard disk drives provide a blend of performance, capacity, and reliability. With their fast spindle speeds, robust data throughput via SAS technology, and enhanced cache memory, these drives are ideal for enterprises requiring durable and efficient data storage solutions in high-demand environments. As organization needs evolve, these drives offer scalability and reliability to support diverse applications and workloads.
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