Data processing system, data processing method and program

Abstract

In the host, an IP issues CCW, and a CH encodes the CCW and a CCW chain by the encode program to create a code including the description of controlling a conditional branch with the DKC and transmits the code to a PORT in the DKC. In the DKC, the PORT decodes the code by the decode program, and a CP sequentially processes each command obtained by the decoding and returns a return code representing the end state of the processing. The host receives the return code to recognize the end state of the processing.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] The present application claims priority from Japanese Patent Application No. JP 2005-98971 filed on Mar. 30, 2005, the content of which is hereby incorporated by reference into this application. [0002] 1. Technical Field of the Invention [0003] The present invention relates to a data processing system to perform a command processing between data processing apparatuses, especially relates to a technology for processing commands and relevant data between a storage control unit such as a disk control unit (referred to as a DKC) in a disk array apparatus (referred to as a storage apparatus) and a host computer (referred to as a host). [0004] 2. Background of the Invention [0005] Conventionally, in the data processing system wherein the host and the disk array apparatus is connected through the channel for communication, generally, the host issues and transmits CCW (channel command word) to the DKC to make the DKC perform the command processi...

AI Technical Summary

Benefits of technology

[0011] The present invention has been made in consideration of the above-mentioned problem. An object of the present invention is to provide a technology used in a data processing system wherein a first data processing apparatus such as the host to issue the command and a second data processing apparatus such as the DKC to process the command are communicatively connected. By collectively processing the group of a plurality of command words (CW) including the conditional branch at the first data processing apparatus and the second data processing apparatus, the load on the processing including CW transfer between the first and second data processing apparatuses is reduced to improve the process performance.

[0023] The following is a brief description of the effects obtained from the representative elements of the invention disclosed in this application. According to the present invention, in the data processing system in which the first data processing apparatus such as the host to issue the command and the second data processing apparatus such as the DKC to process commands are communicatively connected, the first and second data processing apparatuses performs batch-processing for a group of a plurality of command words (CWs) including the conditional branch. Thus the load on the process including transferring of the CW between the first data processing apparatus and the second data processing apparatus can be reduced and the process performance can be improved.

Problems solved by technology

Thus the channel between the host and the DKC is burdened with overhead and the traffic on the path is increased.

Therefore, the above method can not collectively transfer a plurality of CCWs through the path of the channel.

Additionally, when the DKC processes the plurality of CCWs including the conditional branch, it is difficult to determine the position at which the process is ended in the program.

Therefore, the host can not know whether the process is normally performed for each CCW of the CCW chain.

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