Read-ahead Cache, Data buffer structure | Fujitsu MHW2060AC specification

Operations

6.4 Read-ahead Cache

Read-ahead Cache is the function for automatically reading data blocks upon completion of the read command in order to read data from disk media and save data block on a data buffer.

If a subsequent command requests reading of the read-ahead data, data on the data buffer can be transferred without accessing the disk media. As the result, faster data access becomes possible for the host.

6.4.1 DATA buffer structure

This device contains a data buffer. This buffer is divided into two areas: one area is used for MPU work, and the other is used as a read cache for another command. (See Figure 6.7)

8MB buffer (8,388,608 bytes)

8,388,608 bytes

For MPU work	For R/W command

Figure 6.7 Data buffer structure

The read-ahead operation is done by the following commands.

•READ SECTOR(S) (EXT)

•READ MULTIPLE (EXT)

•READ DMA (EXT)

•READ SECTOR(S) EXT

•READ DMA EXT

•READ MULTIPLE EXT

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C141-E258

MHW2060AC, MHW2040AC specifications

The Fujitsu MHW2040AC and MHW2060AC are notable hard disk drives (HDDs) that have been widely used in various computing applications, especially in laptops and compact devices. These models are part of Fujitsu's commitment to providing reliable storage solutions that meet the demands of modern computing.

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In summary, the Fujitsu MHW2040AC and MHW2060AC are reliable, efficient, and user-friendly hard disk drives that combine moderate capacities with advanced features designed to enhance performance, ensure data integrity, and extend device longevity. These drives are well-suited for a range of applications, making them a solid choice for users seeking dependable storage solutions.

Fujitsu MHW2060AC, MHW2040AC Read-ahead Cache, Data buffer structure, 8MB buffer 8,388,608 bytes

Models: MHW2060AC MHW2040AC