Abstract: A tunable processor performance benchmarking method and system (100) estimates candidate software performance on a target processing environment (104) without porting the application. The candidate software's resource consumption is characterized to determine cache hit or miss rates. A test software generator (102) generates test software that is configured to have substantially the same cache miss rates and processor utilization, and its performance is measured when executing on the target processing environment (104). Instruction cache hit rates are maintained for the test software by selectively branching either within a routine (308, 310) that is resident in the instruction cache or to a routine (308, 310) that is not within the instruction cache. Data blocks (332, 334) are also selectively accessed in order to maintain a desired data cache miss rate.