A method of adjustably generating multiple dimensions of computer resource load to test capacity of the multiple dimensions of the computer resource load, the method comprising: executing, on a first computer (19, 20), a utilization test (22a, 22z) that generates the multiple dimensions of resource load (206, 216, 226, 236) on the first computer, the multiple dimensions including at least two of: a processor utilization dimension, a main memory utilization dimension, a mass storage utilization dimension, and a network utilization dimension, wherein, for each dimension of two or more of the multiple dimensions, the utilization test performs iterations of generating a load in said each dimension of the resource load on the first computer, in an amount predicted to cause an actual utilization equal to a changeable target utilization (208, 218, 228, 238) of said each dimension on the first computer, wherein the utilization test measures the actual utilization of a particular one of the multiple dimensions during generation of the resource load on the first computer, the actual utilization being a result of at least: a load generated for the particular one of the multiple dimensions on the first computer, as generated by the utilization test; and a first utilization contribution to the particular one of the multiple dimensions on the first computer, wherein the first utilization contribution is generated outside the utilization test and on the first computer, and wherein the utilization test adjusts the generated load (23a, 23z) to attempt to realize and maintain the target utilization (FIGS. 8-12) on the first computer for said particular one of the multiple dimensions by correcting for an inequality between (i) the actual utilization resulting from the load generated and the first utilization contribution, and (ii) the changeable target utilization of the particular one of the multiple dimensions on the first computer. executing, on a first computer (19, 20), a utilization test (22a, 22z) that generates the multiple dimensions of resource load (206, 216, 226, 236) on the first computer, the multiple dimensions including at least two of: a processor utilization dimension, a main memory utilization dimension, a mass storage utilization dimension, and a network utilization dimension, wherein, for each dimension of two or more of the multiple dimensions, the utilization test performs iterations of generating a load in said each dimension of the resource load on the first computer, in an amount predicted to cause an actual utilization equal to a changeable target utilization (208, 218, 228, 238) of said each dimension on the first computer, wherein the utilization test measures the actual utilization of a particular one of the multiple dimensions during generation of the resource load on the first computer, the actual utilization being a result of at least: a load generated for the particular one of the multiple dimensions on the first computer, as generated by the utilization test; and a first utilization contribution to the particular one of the multiple dimensions on the first computer, wherein the first utilization contribution is generated outside the utilization test and on the first computer, and a load generated for the particular one of the multiple dimensions on the first computer, as generated by the utilization test; and a first utilization contribution to the particular one of the multiple dimensions on the first computer, wherein the first utilization contribution is generated outside the utilization test and on the first computer, and wherein the utilization test adjusts the generated load (23a, 23z) to attempt to realize and maintain the target utilization (FIGS. 8-12) on the first computer for said particular one of the multiple dimensions by correcting for an inequality between (i) the actual utilization resulting from the load generated and the first utilization contribution, and (ii) the changeable target utilization of the particular one of the multiple dimensions on the first computer.