Two major trends in high-performance computing, namely, larger numbers of cores and the growing size of on-chip cache memory, are creating significant challenges for evaluating the design space of future processor architectures. Fast and scalable simulations are there- fore needed to allow for sufficient exploration of large multi-core systems within a limited simulation time budget. By bringing together accurate high-abstraction analytical models with fast parallel simulation, architects can trade off accuracy with simulation speed to allow for longer application runs, covering a larger portion of the hardware design space. Sniper provides this balance allowing long-running simulations to be modeled much faster than with detailed cycle-accurate simulation, while still providing the detail necessary to observe core-uncore interactions across the entire system. With per-function advanced visualization and coupled power and energy simulations, the Sniper multi-core simulator can provide a fast and accurate way both to understand and optimize software for current and future hardware systems.