4.1 Mode Parameters

a.RCD (read cache disable)

This bit can be specified, and its operation is as specified.

This bit specifies whether or not to activate the cache operation for a read command.

"1" : Prohibits operation of the Look-Ahead cache function.

The IDD reads ahead all of the data requested by the READ command or READ EXTENDED command from the disk and transfers it to the INIT. Moreover, it does not read ahead data blocks after the requested data.

"0" : Specifies operation of the Look-Ahead cache function.

If part or all of the data, including logical data blocks of headers, requested by a READ command or READ EXTENDED command exists in the data buffer, the IDD transfers that data without accessing the disk. Also, depending on the instructions for the bytes beyond byte 4 of the parameter page, it reads ahead the data blocks after the requested data in the data buffer.

b.Multiple selection (MS)

This bit specifies how to specify the "minimum prefetch count" (bytes 6 and 7) and "maximum prefetch count" (bytes 8 and 9) parameters in this page descriptor.

1:The "minimum prefetch count" and "maximum prefetch count" parameters indicate a multiplier. The number of data blocks to be prefetch is calculated that the value in the "transfer byte count" in the CDB specified by the READ or READ EXTENDED command X multiplier.

0:The "minimum prefetch count" and "maximum prefetch count" parameters indicate the data block count to be prefetched with the logical data block count.

This bit cannot be changed, and the IDD ignores this bit specification and operates according to the default value ('0').

c.WCE (write cache enable)

This bit can be specified, and its operation is as specified.

This bit specifies whether or not to activate the cache operation for a write command.

"1" : This enables the write cache.

Write data remains in the buffer memory, the cache is made the object even for a read command, and when all of the write data has been received, "GOOD" status is reported without disconnecting.

Sequential writing is performed without waiting for rotation.

"0" : This prohibits operation of the write cache function.

Write data remains in the buffer memory, the cache is not made the object even for a read command, and as soon as all the data has been written to the disk, "GOOD" status is reported.

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Fujitsu MAS3367, MAP3367, MAP3147, MAS3735, MAP3735 specifications Mode Parameters
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MAP3735, MAP3147, MAS3367, MAP3367, MAS3735 specifications

Fujitsu, a renowned leader in technology and innovation, has developed a variety of reliable hard disk drives (HDDs) that cater to a wide range of data storage needs. Among these, the MAS3735, MAP3367, MAS3367, MAP3147, and MAP3735 series stand out for their advanced features and exceptional performance.

The MAS3735 is a high-capacity enterprise-class drive that boasts a storage capacity of up to 300 GB. Its 10,000 RPM spindle speed ensures rapid data retrieval and efficient performance, making it ideal for data-intensive applications. It utilizes a Serial Attach SCSI (SAS) interface, which allows for improved data transfer rates and increased reliability compared to traditional SATA drives. The drive is designed with advanced technologies such as error recovery and data integrity features, ensuring the safety and security of critical data.

Similarly, the MAP3367 and MAS3367 models are geared towards both enterprise and mid-range server environments, providing a storage capacity of up to 300 GB as well. These drives also operate at a spindle speed of 15,000 RPM, offering swift access times that enhance overall system performance. The MAP3367 employs the Ultra 320 SCSI interface, allowing for significant bandwidth and ensuring data is transmitted efficiently.

On the other hand, both MAP3147 and MAP3735 models provide versatile solutions for various applications, supporting capacities from 36 GB to 147 GB. The MAP3147, with its 10,000 RPM speed, is optimized for workloads requiring quick access and high throughput, making it suitable for transactional systems and enterprise applications. The MAP3735, while offering comparable capacity, emphasizes exceptional reliability and durability, which is crucial for environments that involve heavy data loads.

All these Fujitsu HDDs are characterized by their robust construction, reliability, and efficiency. They are built to withstand heavy workloads and are equipped with features like advanced thermal management and acoustic noise reduction, ensuring they operate effectively in data center environments.

In conclusion, Fujitsu's MAS3735, MAP3367, MAS3367, MAP3147, and MAP3735 series HDDs are designed for high performance and reliability, catering to both enterprise and mid-range environments. Their advanced features make them a strong choice for businesses looking to enhance their storage solutions while maintaining data integrity and system performance.
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