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Fujitsu MAS3735, MAP3367, MAP3147, MAP3735, MAS3367 Look-Ahead Cache Feature, Read Read Extended

Models: MAP3735 MAP3147 MAS3367 MAP3367 MAS3735

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2.2 Look-Ahead Cache Feature

(1)Caching object commands

Commands which execute caching operations are the commands shown below:

•READ

•READ EXTENDED

If all the data block groups which are objects of the processing specified in these commands, or a portion of the data blocks, including the top logical data block specified in these commands are relevant data (See item (2)) for caching in the data buffer (if they hit), when the IDD receives a command and performs disconnect processing, it immediately reconnects and sends the data on the data buffer which can be transferred to the INIT. The caching operation can be disabled by the FUA bit of the READ EXTENDED command. If "1" is specified in the FUA bit, the IDD reads data from the disk media.

On the other hand, if the top logical data block specified in a command is not relevant data for caching in the data buffer (if they miss), reading of data is performed from the disk media using the old cache segment.

(2)Data which are objects of caching

Data which exist in the data buffer and which are objects of caching in item (1) (data which are not accessed from the disk media but are transferred to the INIT from the data buffer) are as described below.

a)Data read by a READ or a READ EXTENDED command and which have been read to the data buffer by Look-Ahead are data which are objects of caching. Depending on the timing for halting Look-Ahead, it is possible that data read by the READ command will be overwritten by Look-Ahead.

b)Data which have been hit by the READ or READ EXTENDED command and transferred to the INIT once are also objects of caching as long as they are not invalidated.

c)Data transferred from the INIT and written to the disk media by the WRTTE and WRITE EXTENDED command are objects of caching.

d)Data transferred from the INIT and written to the disk media by the WRITE AND VERIFY command is not the objects of caching.

(3)Disabling caching data

Various data which are objects of caching in the data buffer are disabled in the following cases.

a)If any of the following commands is issued for the same data block as data which are the object of caching, that data block ceases to be an object of caching.

• WRITE

• WRITE AND VERIFY

•WRITE EXTENDED

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Fujitsu MAS3735, MAP3367, MAP3147 Look-Ahead Cache Feature, Read Read Extended, Write Write and Verify Write Extended
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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.