Controlling storage accesses for merge operations
Storage accesses for merge operations are minimized. A plurality of records of a plurality of input lists are merged. The merging includes determining that an input list of the plurality of input lists has become empty, and checking, based on determining that the input list has become empty, a control specific for the input list. The control is used to determine how to proceed, such as whether to end merging or continue merging.
1. A computer program product for facilitating processing within a computing environment, the computer program product comprising:
at least one computer readable storage medium readable by at least one processor and storing instructions for performing a method comprising:
merging, by one or more processors, a plurality of records of a plurality of input lists, wherein the merging includes:
determining that an input list of the plurality of input lists has become empty;
obtaining a control to be checked based on the input list becoming empty, the control being an input to the merging and being set prior to the merging and not updated during the merging, the control including:
one indicator having one or more bits, the one indicator of the control being assigned to a selected input list of the plurality of input lists to control processing based on the selected input list becoming empty during the merging; and
another indicator, separate from the one indicator and having one or more other bits, the another indicator of the control being assigned to remaining input lists of the plurality of input lists, the remaining input lists excluding the selected input list, and the another indicator of the control to control processing based on a remaining input list of the remaining input lists becoming empty during the merging;
determining that the input list that has become empty is the selected input list of the plurality of input lists;
checking, based on determining that the selected input list has become empty, the one indicator of the control specifically assigned to the selected input list to determine how to proceed based on the selected input list becoming empty during the merging; and
performing processing, based on the one indicator of the control that is set prior to merging and not updated during the merging, wherein the one indicator of the control is set to one value indicates that the merging is to continue based on the selected input list becoming empty.
2. The computer program product of claim 1 , wherein based on the one indicator of the control being set to another value, the merging is to end based on the selected input list becoming empty.
3. The computer program product of claim 1 , wherein the remaining input list has become empty during the merging and the another indicator of the control set to a selected value indicates that the merging is to end based on the remaining input list becoming empty during the merging.
4. The computer program product of claim 1 , wherein the control is included in a parameter block that is input to the merging and used by the merging.
5. The computer program product of claim 1 , wherein the method further comprises:
determining that an indication of the input list that has become empty is to be stored in a select location, the determining being based, at least in part, on the control; and
storing the indication of the input list in the select location, based on the determining specifying that the indication is to be stored.
6. The computer program product of claim 5 , wherein the determining that the indication is to be stored comprises checking another control, the other control set to a select value indicates the indication is to be stored in the select location, the other control being set, based in part, on the control.
7. The computer program product of claim 6 , wherein the method further comprises setting the other control, the setting comprising:
checking that the control is a defined value; and
determining that a particular condition code has been set, wherein the other control is set to the select value based on the control being the defined value and the particular condition code being set.
8. The computer program product of claim 1 , wherein the control is specified by an instruction and set prior to commencing the merging.
9. The computer program product of claim 8 , wherein the instruction comprises a sort instruction, the sort instruction being defined based on a selected instruction set architecture.
10. A computer system for facilitating processing within a computing environment, the computer system comprising:
a memory; and
a processor in communication with the memory, wherein the computer system is configured to perform a method comprising:
merging, by one or more processors, a plurality of records of a plurality of input lists, wherein the merging includes:
determining that an input list of the plurality of input lists has become empty;
obtaining a control to be checked based on the input list becoming empty, the control being an input to the merging and being set prior to the merging and not updated during the merging, the control including:
one indicator having one or more bits, the one indicator of the control being assigned to a selected input list of the plurality of input lists to control processing based on the selected input list becoming empty during the merging; and
another indicator, separate from the one indicator and having one or more other bits, the another indicator of the control being assigned to remaining input lists of the plurality of input lists, the remaining input lists excluding the selected input list, and the another indicator of the control to control processing based on a remaining input list of the remaining input lists becoming empty during the merging;
determining that the input list that has become empty is the selected input list of the plurality of input lists;
checking, based on determining that the selected input list has become empty, the one indicator of the control specifically assigned to the selected input list to determine how to proceed based on the selected input list becoming empty during the merging; and
performing processing, based on the one indicator of the control that is set prior to merging and not updated during the merging, wherein the one indicator of the control set to one value indicates that the merging is to continue based on the selected input list becoming empty.
11. The computer system of claim 10 , wherein based on the one indicator of the control being set to another value, the merging is to end based on the selected input list becoming empty.
12. The computer system of claim 10 , wherein the control is included in a parameter block that is input to the merging and used by the merging.
13. The computer system of claim 10 , wherein the method further comprises:
determining that an indication of the input list that has become empty is to be stored in a select location, the determining being based, at least in part, on the control; and
storing the indication of the input list in the select location, based on the determining specifying that the indication is to be stored.
14. The computer system of claim 13 , wherein the determining that the indication is to be stored comprises checking another control, the other control set to a select value indicates the indication is to be stored in the select location, the other control being set, based in part, on the control.
15. A computer-implemented method of facilitating processing within a computing environment, the computer-implemented method comprising:
merging, by at least one processor, a plurality of records of a plurality of input lists, wherein the merging includes:
determining that an input list of the plurality of input lists has become empty;
obtaining a control to be checked based on the input list becoming empty, the control being an input to the merging and being set prior to the merging and not updated ring the merging, the control including:
one indicator having one or more bits, the one indicator of the control being assigned to a selected input list of the plurality of input lists to control processing based on the selected input list becoming empty during the merging; and
another indicator, separate from the one indicator and having one or more other bits, the another indicator of the control being assigned to remaining input lists of the plurality of input lists, the remaining input lists excluding the selected input list, and the another indicator of the control to control processing based on a remaining input list of the remaining input lists becoming empty during the merging;
determining that the input list that has become empty is the selected input list of the plurality of input lists;
checking, based on determining that the selected input list has become empty, the one indicator of the control specifically assigned to the selected input list to determine how to proceed based on the selected input list becoming empty during the merging; and
performing processing, based on the one indicator of the control that is set prior to merging and not updated during the merging, wherein the one indicator of the control set to one value indicates that the merging is to continue based on the selected input list becoming empty.
16. The computer-implemented method of claim 15 , wherein based on the one indicator of the control being set to another value, the merging is to end based on the selected input list becoming empty.
17. The computer-implemented method of claim 15 , wherein the control is included in a parameter block that is input to the merging and used by the merging.
18. The computer-implemented method of claim 15 , further comprising:
determining that an indication of the input list that has become empty is to be stored in a select location, the determining being based, at least in part, on the control; and
storing the indication of the input list in the select location, based on the determining specifying that the indication is to be stored.
19. The computer-implemented method of claim 18 , wherein the determining that the indication is to be stored comprises checking another control, the other control set to a select value indicates the indication is to be stored in the select location, the other control being set, based in part, on the control.
20. The computer-implemented method of claim 15 , wherein the control is specified by an instruction and set prior to commencing the merging.
21. A computer program product for facilitating processing within a computing environment, the computer program product comprising:
at least one computer readable storage medium readable by at least one processor and storing instructions for performing a method comprising:
merging, by one or more processors, a plurality of records of a plurality of input lists, wherein the merging includes:
determining that an input list of the plurality of input lists has become empty;
obtaining a control to be checked based on the input list becoming empty, the control being an input to the merging and being set prior to the merging and not updated during the merging, the control including:
one indicator having one or more bits, the one indicator of the control being assigned to a selected input list of the plurality of input lists to control processing based on the selected input list becoming empty during the merging; and
another indicator, separate from the one indicator and having one or more other bits, the another indicator of the control being assigned to remaining input lists of the plurality of input lists, the remaining input lists excluding the selected input list, and the another indicator of the control to control processing based on a remaining input list of the remaining input lists becoming empty during the merging;
determining that the input list that has become empty is the remaining input list of the remaining input lists;
checking, based on determining that the remaining input list has become empty, the another indicator of the control specifically assigned to the remaining input lists to determine how to proceed based on the remaining input list becoming empty during the merging; and
continuing merging, based on the another indicator of the control that is set prior to merging and not updated during the merging being set to one value indicating that the merging is to continue based on the remaining input list becoming empty.
22. The computer program product of claim 21 , wherein based on the another indicator of the control being another value, the merging is to end based on the remaining input list becoming empty.
23. A computer program product for facilitating processing within a computing environment, the computer program product comprising:
at least one computer readable storage medium readable by at least one processor and storing instructions for performing a method comprising:
merging, by one or more processors, a plurality of records of a plurality of input lists, wherein the merging includes:
determining that an input list of the plurality of input lists has become empty;
obtaining a control to be checked based on the input list becoming empty, the control being an input to the merging and being set prior to the merging and not updated during the merging, the control including:
one indicator having one or more bits, the one indicator of the control being assigned to a selected input list of the plurality of input lists to control processing based on the selected input list becoming empty during the merging; and
another indicator, separate from the one indicator and having one or more other bits, the another indicator of the control being assigned to remaining input lists of the plurality of input lists, the remaining input lists excluding the selected input list, and the another indicator of the control to control processing based on a remaining input list of the remaining input lists becoming empty during the merging;
determining that the input list that has become empty is the selected input list of the plurality of input lists;
checking, based on determining that the selected input list has become empty, the one indicator of the control specifically assigned to the selected input list to determine how to proceed based on the selected input list becoming empty during the merging;
continuing merging, based on the one indicator of the control that is set prior to merging and not updated during the merging being set to one value indicating that the merging is to continue based on the selected input list becoming empty; and
storing an indication of the input list that has become empty, based on determining that a particular condition code has been set and that another control is set to a selected value.
24. The computer program product of claim 23 , wherein the method further comprises:
determining that the indication of the input list that has become empty is to be stored in a select location, the determining comprising checking the another control, the another control set to the selected value indicates the indication is to be stored in the select location, the another control being set, based in part, on the control.
25. The computer program product of claim 24 , wherein the method further comprises setting the another control, the setting comprising:
checking that the control is a defined value; and
determining that the particular condition code has been set, wherein the another control is set to the selected value based on the control being the defined value and the particular condition code being set.