Operations

6.4.3.2 Sequential hit

When the read command that is targeted at a sequential address is received after execution of the read commands is completed, the read command transmits the Read requested data to the host system continuing read-ahead without newly allocating the buffer for read.

1)When the sequential read command is received, HAP is set in the sequential address of the last read command, and DAP is set at a present read position as it is.

 

HAP (host address pointer)

 

 

 

 

 

 

Cache valid data

 

Read requested data

Free space

 

Read-ahead da

ta

 

 

 

DAP (disk address pointer)

2)During reading of read requested data, the request data that has already been read is sent to the host system.

HAP (host address pointer)

Cache valid data

Read requested data

Free space

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DAP (disk address pointer)

3)When reading of read requested data is completed and transfer of the read requested data to the host system is completed, the read-ahead operation continues until a certain amount of data is stored.

HAP (host address pointer)

Cache valid data

Read requested data

Read-ahead

Free

data

space

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DAP (disk address pointer)

4) The following cache valid data is for the read command that is executed next:

Cache valid data

LAST LBA START LBA

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Fujitsu MHW2060AC, MHW2040AC manual Sequential hit

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.

The MHW2040AC offers a storage capacity of 40 GB, while the MHW2060AC provides a slightly larger capacity at 60 GB. This range of storage makes both models suitable for users looking for dependable space for documents, multimedia files, and software applications. Both drives utilize a 2.5-inch form factor, ideal for mobile computing, as they are lightweight and designed to fit into space-constrained environments.

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The MHW2040AC and MHW2060AC also incorporate several advanced technologies to bolster their performance and reliability. One such feature is the use of a fluid dynamic bearing (FDB) for the spindle motor, which minimizes noise and vibration, thus improving the overall user experience. Additionally, both drives come with error correction technology that helps maintain data integrity by detecting and correcting errors during read and write operations.

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