The dataset is provided as a .zip archive containing two .csv data files. These two data files contain the results of a series of timing runs made with a suite of 28 C test programs and 20 C++ test programs using three different computers and two operating systems (Windows and Linux). All 48 test programs carry out processing of two-dimensional arrays. One of the files, "C_CppTimeTestsAllRecords.csv", contains three replicated times for each of 960 combinations of factor levels that potentially might have affected the time required to process two-dimensional arrays. The other file, "C_CppTimeTestsAverages.csv", contains the average of the three replicated times for each of the 960 combinations of factor levels. Both files have the same column headers and data formats, and the meaning of the data fields (columns) is the same in both files, with one exception. The exception is that the file for all records contains actual runtimes (in seconds) in the "ProcTime" field, whereas the other file contains averaged runtimes in the "ProcTime" field.