Fujitsu MHY2040BS Manuale Utente

 

In this situation, all read requested data is stored in the data buffer.  Transfer of the 
read requested data is started from the location where hit data is stored.  For data 
that is a target of caching and remains before a full hit, the data is retained when 
execution of the command is completed.  This is done so that a new read-ahead 
operation is not performed.  If the full hit command is received during the read-
ahead operation, a transfer of the read requested data starts while the read-ahead 
operation is in progress. 

1)  An example is the state shown below where the previous read command is 

executing sequential reading.  First, HAP is set at the location where hit data 
is stored. 

HAP (It is reset to the hit data location for transfers.)

HAP end location of the previous read command

DAP end location of the previous read command

Cache data

Full hit data

Cache data

HAP

DAP

 

2)  The read requested data is transferred, and a new read-ahead operation is not 

performed. 

(stop)

HAP

Cache data

Full hit data

Cache data

 

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C141-E269