1. A computer program product for implementing non-default instruction handling within a transaction, the computer program product comprising: a computer readable storage medium having program instructions embodied therewith, the program instructions readable by a processing circuit to cause the processing circuit to perform a method comprising: entering a transaction, the transaction comprising a first plurality of instructions and a second plurality of instructions, wherein the transaction includes a default manner of handling of instructions in the transaction; encountering a non-default specification instruction in the transaction, wherein the non-default specification instruction comprises a single instruction that specifies the second plurality of instructions of the transaction for handling in a non-default manner, wherein the non-default manner is different from the default manner, wherein the non-default specification instruction further specifies that the second plurality of instructions comprises one of only read instructions or only write instructions; handling the first plurality of instructions in the default manner; and handling the second plurality of instructions in the non-default manner.