An emulator for approximate memory platforms based on QEmu

In this paper, an emulation environment for approximate memory architectures is presented. In the context of error tolerant applications, in which energy is saved at the expense of the occurrence of errors in data processing, approximate memories play a relevant part. Approximate memories are memories where read/write errors are allowed with controlled probability. In general these errors are the result of circuital or architectural techniques (i.e. voltage scaling, refresh rate reduction) introduced to save energy. The ability to simulate these systems is particularly important since the amount of tolerated error is application dependent. Simulation allows to analyze the behavior of an application and explore its tolerance to actual error rates, determining the trade-off between saved energy and output quality. We have developed an emulation environment for such architectures, based on QEmu, which allows the execution of programs that can allocate some of their data in a memory zone subject to faults.We present the emulated architecture, the fault injection model and a case of study showing results that can be obtained by our emulator.