is performed when it becomes possible to transfer 2 blocks of data [16 x (32/256)], from the data buffer.

b.Buffer empty ratio

This parameter specifies the timing for the IDD to start reconnection when it is requested by the INIT to transfer data in the WRITE, WRITE EXTENDED or WRITE AND VERIFY command. In a write operation, after the IDD receives a command, the IDD begins transferring data (data pre-fetch) while locating the position of the target data blocks on the disk media in parallel. Therefore, if the total number of bytes of data specified in the command is less than the capacity of a cache segment, all the data are pre-fetched in a batch, so the specification in this parameter is not applied.

The value specified in this parameter (n) indicates a proportion of the total data buffer capacity of the IDD when the buffer is empty [n/256]. (Note)

While the IDD is writing data to the disk media, it is using the data pre-fetched to the data buffer in order and when the empty space in the data buffer reaches the amount specified in this parameter, it executes reconnection processing, requesting transfer of the succeeding data. However, if the number of data blocks remaining to be transferred according to the command being executed does not reach the amount of data specified in this parameter, the IDD executes reconnection processing at the point when the number of data blocks remaining in the data buffer's empty space reaches the specified number of data blocks and requests transfer of the succeeding data.

Note:

If the value specified for the "buffer full ratio" or the "buffer empty ratio" is not within double the integral boundary of the logical data block length, the IDD rounds up the specified value to the nearest data block boundary. In addition, if zero is specified for any of these parameters, the IDD an appropriate value for the parameter that is determind by IDD.

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Fujitsu MAN3184, MAN3367, MAN3735 SERIES DISK DRIVES specifications

MAN3735, MAN3184, MAN3367, MAN3735 SERIES DISK DRIVES, MAN3367, MAN3184 specifications

Fujitsu's MAN3184, MAN3367, and MAN3735 series disk drives represent a significant advancement in storage technology, catering to the needs of businesses seeking reliability, performance, and high capacity. These drives are designed for enterprise environments, providing exceptional data integrity and speed essential for effective data management.

The MAN3184 series is renowned for its high rotational speed of 10,000 RPM, which significantly enhances data access times. With a capacity of up to 18.4 GB, these drives are suitable for applications requiring quick read and write operations. The series employs an improved read/write head technology, which reduces latency and increases overall performance. This technology is complemented by advanced error correction mechanisms, ensuring the reliability necessary for critical data applications.

Transitioning to the MAN3367 series, these drives offer increased storage capacity and improved performance metrics. With capacities reaching up to 36.7 GB, they cater to growing data demands in modern enterprises. They also feature a 10,000 RPM spindle speed, ensuring that the drives can handle intensive workloads with ease. The MAN3367 drives include SCSI interface support, making them versatile and easy to integrate into various systems. The inclusion of intelligent caching algorithms allows for faster data retrieval, while built-in thermal management features ensure optimal performance, even under heavy usage.

The MAN3735 series takes performance up another notch, boasting higher capacities of up to 73.5 GB. These drives are particularly suited for environments that require high reliability and availability. The series utilizes a state-of-the-art SCSI Ultra160 interface, which maximizes data transfer rates, ultimately enhancing overall system efficiency. Additionally, the MAN3735 series employs advanced data protection technologies, including power loss protection and predictive failure analysis, which proactively minimizes potential downtime.

All these series of Fujitsu disk drives are built with a focus on durability and sustained performance. They are designed to operate seamlessly in high-demand environments, ensuring that organizations can rely on them for critical applications. Their compact design and energy-efficient operation make them an ideal choice for modern data centers looking to optimize space and reduce power consumption.

In summary, Fujitsu's MAN3184, MAN3367, and MAN3735 series disk drives deliver a blend of high capacity, performance, and reliability. These drives incorporate advanced technologies that address the evolving needs of enterprise storage solutions, making them a valuable asset for any organization aiming to enhance their data management capabilities.