A method for testing a computer system , the method comprising: receiving, at a processor, script information that includes dimension-effect values, a first dimension-effect value corresponding to a rate at which a first dimension (315; 410; 515) is affected by a first script (105; 310; 512) per execution of the first script and a second dimension-effect value corresponding to a rate at which a second dimension (315; 410; 515) is affected by a second script (105; 310; 512) per execution of the second script, wherein the first and second test scripts simulate human interactions with the computer system, the first dimension (315; 410; 515) corresponds to a first operation of the computer system that is exercisable by the first script and the second dimension (315; 410; 515) corresponds to a second operation of the computer system that is exercisable by the second script; receiving, at the processor, target-dimension values, each target-dimension value corresponding to a desired number of times per time period the first and second dimensions should be affected by the first and second scripts; determining a first number of times to execute the first script within the time period and a second number of times to execute the second script within the time period, so as to minimize the difference between actual number of times the first and second dimensions are affected and the target-dimension values per time period for the first and second dimensions, wherein the first number of times is different from the second number of times; and causing execution of the first script on the computer system the determined first number of times within the time period and causing execution of the second script on the computer system the determined second number of times within the time period. receiving, at a processor, script information that includes dimension-effect values, a first dimension-effect value corresponding to a rate at which a first dimension (315; 410; 515) is affected by a first script (105; 310; 512) per execution of the first script and a second dimension-effect value corresponding to a rate at which a second dimension (315; 410; 515) is affected by a second script (105; 310; 512) per execution of the second script, wherein the first and second test scripts simulate human interactions with the computer system, the first dimension (315; 410; 515) corresponds to a first operation of the computer system that is exercisable by the first script and the second dimension (315; 410; 515) corresponds to a second operation of the computer system that is exercisable by the second script; receiving, at the processor, target-dimension values, each target-dimension value corresponding to a desired number of times per time period the first and second dimensions should be affected by the first and second scripts; determining a first number of times to execute the first script within the time period and a second number of times to execute the second script within the time period, so as to minimize the difference between actual number of times the first and second dimensions are affected and the target-dimension values per time period for the first and second dimensions, wherein the first number of times is different from the second number of times; and causing execution of the first script on the computer system the determined first number of times within the time period and causing execution of the second script on the computer system the determined second number of times within the time period. <EOS>