Adaptive Read Ahead Method of Data Recorded on a Sequential Media Readable via a Variable Data Block Size Storage Device

Abstract

A read request of a sequential media from a host is executed with a read request data block size equal to a maximum recorded data block size parameter of the variable data block size storage device. Subsequently, if warranted, an adaptive read ahead data block size variable is set to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request, and one or more read ahead requests of the sequential media are executed with a read ahead data block size equal to the adaptive read ahead data block size variable. The adaptive read ahead data block size variable is conditionally adjusted based on the recorded data block size(s) of data recorded on the sequential media that is responsive to the execution(s) of the read ahead request(s)

1 . A signal bearing medium tangibly embodying a program of machine-readable instructions executable by a processor to perform operations to implement an adaptive read ahead method of a sequential media readable via a variable data block size storage device, the operations comprising: executing a read request of the sequential media in response to an electrical communication of the read request from a host, wherein the read request is executed with a read request data block size equal to a maximum recorded data block size parameter of the variable data block size storage device; and subsequent to the execution of the read request of the sequential media, setting an adaptive read ahead data block size variable to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request.  
   
   
       2 . The signal bearing medium of  claim 1 , wherein the operations further comprise: subsequent to the execution of the read request of the sequential media, executing a read ahead request of the sequential media with a read ahead data block size equal to the adaptive read ahead data block size variable; and subsequent to the execution of the read ahead request of the sequential media, conditionally setting the adaptive read ahead data block size variable to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request.  
   
   
       3 . The signal bearing medium of  claim 2 , wherein conditionally setting the adaptive read ahead data block size variable to equal the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request includes: retaining the setting of the adaptive read ahead data block size variable equal to the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request in response to determining the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request equals the setting of the adaptive read ahead data block size variable.  
   
   
       4 . A system, comprising: a processor; and a memory storing instructions operable with the processor for implementing an adaptive read ahead of a sequential media readable via a variable data block size sequential storage device, the instructions are executed for executing a read request of the sequential media in response to an electrical communication of the read request from a host, wherein the read request is executed with a read request data block size equal to a maximum recorded data block size parameter of the variable data block size storage device; and subsequent to the execution of the read request of the sequential media, setting an adaptive read ahead data block size variable to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request.  
   
   
       5 . The system of  claim 4 , wherein the instructions are further executed for: subsequent to the execution of the read request of the sequential media, executing a read ahead request of the sequential media with a read ahead data block size equal to the adaptive read ahead data block size variable; and subsequent to the execution of the read ahead request of the sequential media, conditionally setting the adaptive read ahead data block size variable to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request.  
   
   
       6 . The system of  claim 5 , wherein conditionally setting the adaptive read ahead data block size variable to equal the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request includes: retaining the setting of the adaptive read ahead data block size variable equal to the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request in response to determining the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request equals the setting of the adaptive read ahead data block size variable.  
   
   
       7 . A method for implementing an adaptive read ahead of a sequential media readable via a variable data block size sequential storage device, the method comprising: executing a read request of the sequential media in response to an electrical communication of the read request from a host, wherein the read request is executed with a read request data block size equal to a maximum recorded data block size parameter of the variable data block size storage device; and subsequent to the execution of the read request of the sequential media, setting an adaptive read ahead data block size variable to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request.  
   
   
       8 . The method of  claim 7 , further comprising: subsequent to the execution of the read request of the sequential media, executing a read ahead request of the sequential media with a read ahead data block size equal to the adaptive read ahead data block size variable; and subsequent to the execution of the read ahead request of the sequential media, conditionally setting the adaptive read ahead data block size variable to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request.  
   
   
       9 . The method of  claim 8 , wherein conditionally setting the adaptive read ahead data block size variable to equal the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request includes: retaining the setting of the adaptive read ahead data block size variable equal to the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request in response to determining the recorded data block size of data recorded on the sequential media that is responsive to the execution of the read ahead request equals the setting of the adaptive read ahead data block size variable.