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Partial Performing of Synchronous Instructions

IP.com Disclosure Number: IPCOM000120949D
Original Publication Date: 1991-Jun-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 1 page(s) / 51K

Publishing Venue

IBM

Related People

Hefferon, EP: AUTHOR

Abstract

Synchronous CPU instructions are typically defined to either do some defined set of operations or, in the case of a condition or error, to not do that defined set of operations. Presently, if a synchronous instruction terminates during execution, there is no way to tell how far the instruction progressed or what condition things were left in when the instruction terminated. In this case, the work that was partially completed is not useful to the program.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 77% of the total text.

Partial Performing of Synchronous Instructions

      Synchronous CPU instructions are typically defined to either do
some defined set of operations or, in the case of a condition or
error, to not do that defined set of operations.  Presently, if a
synchronous instruction terminates during execution, there is no way
to tell how far the instruction progressed or what condition things
were left in when the instruction terminated. In this case, the work
that was partially completed is not useful to the program.

      Instructions are known which initiate asynchronous operations
that are done independently of the execution of the instruction
itself.  Asynchronous operations can be partially completed and the
program can detect how many of the requested operations were
performed and make use of the partial results.  This disclosure is
directed to the partial performing of those operations that are part
of the execution of synchronous instructions.

      A channel subsystem call (CHSC) instruction is defined which
allows for the instruction to complete normally even though only a
portion of the work that is requested by means of input parameters is
completed.  The amount of work done is based on the implementation
and conditions that exist at the time when CHSC is executed.  The
size of a variable-length-response block stored by CHSC in
conjunction with a response code inform the program how much work was
done.  This mechanism is to be used in the definitions o...