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)

 

 

 

 

 

MAS3735NC/NP

8

 

143,552,136

73.49

 

 

512

 

 

MAS3367NC/NP

4

71,819,496

36.77

 

 

 

 

 

MAS3184NC/NP

2

 

35,890,512

18.37

 

 

 

 

 

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 MAS3367NC/NP, MAS3184NC/NP manual Format capacity, MAS3735NC/NP

MAS3367NC/NP, MAS3184NC/NP, MAS3735NC/NP specifications

Fujitsu's MAS series hard drives, including the MAS3735NC/NP, MAS3184NC/NP, and MAS3367NC/NP, are designed for enterprise applications requiring high performance, reliability, and efficiency. These drives are notable for their ability to manage extensive workloads, making them ideal for demanding server and storage environments.

The MAS3735NC/NP is a 3.5-inch hard drive that operates at 15,000 RPM, providing exceptional data access speeds. With a storage capacity of up to 300GB, this model is optimized for high transaction applications, such as databases and email servers. Its advanced 16 MB buffer ensures that data is managed smoothly, significantly reducing latency and improving overall system performance. The drive employs SAS (Serial Attached SCSI) interface technology, which enhances data transfer rates and provides better reliability compared to traditional SATA interfaces.

The MAS3184NC/NP model features a generous 146GB storage capacity, operating at a slightly lower peak performance of 10,000 RPM. However, it still provides substantial speed and reliability for various server applications. The advanced features of this drive include enhanced error recovery, which minimizes the risk of data corruption, as well as a power-saving mode that reduces energy consumption without compromising performance.

Next in the series, the MAS3367NC/NP offers a combination of capacity and speed. With up to 300GB of storage and also spinning at 15,000 RPM, it matches the performance levels of the MAS3735. This drive utilizes dual-port 6Gb/s SAS technology, which not only boosts data transfer rates but also adds redundancy, thus ensuring continuous availability for mission-critical applications.

All models in this range are designed with advanced technologies such as S.M.A.R.T (Self-Monitoring, Analysis, and Reporting Technology), which helps monitor the drive's health and predict potential failures before they occur. Additionally, these drives are built to meet rigorous environmental and physical standards, ensuring durability and longevity in various applications.

In summary, Fujitsu’s MAS3735NC/NP, MAS3184NC/NP, and MAS3367NC/NP hard drives showcase a perfect blend of speed, capacity, and reliability, solidifying their position as leading choices for enterprise-level storage solutions. With their advanced technologies and features, these drives are tailored for environments where performance and reliability are non-negotiable requirements.