A number starting with 0 is assigned to each cylinder required in the user space in ascending order. If the number of cylinders do not reach the maximum, the rest of the cylinders will not be used.

Always one cylinder that is located at the end of each zone in the user space can be established as an alternate cylinder. Alternate cylinders will be used for alternate blocks when primary cylinders in the user space are used up. See Subsections 3.1.2 and 3.3.2 for details.

(2)Internal test space

The Internal test space is an area for diagnostic purposes only and its data block length is always 512KByte. The Internal test space consists of 8 cylinders and outer-host cylinder is always assigned. The user cannot change the number of cylinders in the Internal test space or their positions.

(3)System space

The system space is an area for exclusive use of the IDD itself and the following information are recorded.

Defect list (P list and G list)

MODE SELECT parameter (saved value)

Statistical information (log data)

Controller control information

The above information is duplicated in several different locations for safety.

Note:

The system space is also called SA space.

3.1.2Alternate spare area

The alternate spare area consists of the last track of each cell in the user space and an alternate cylinder allocated to the last cylinder of each zone.

The spare area in each cylinder is placed at the end of the last track as shown in Figure 3.2. These spare sectors are located in the end of the track logically, not necessarily located at the end physically because of track skew or cylinder skew. (Details are explained on Subsection 3.1.3.)

Size can be specified by the MODE SELECT command.

The number of spare sectors per cell can be specified exceeding 32. The default for the spare sectors number is 84.

3-4

C141-E166

Page 38
Image 38
Fujitsu MAP3735NC/NP, MAP3147NC/NP, MAP3735NP, MAP3367NC/NP, MAP3367NP manual Alternate spare area

MAP3735NP, MAP3367NC, 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.