Automating Stressmark Generation for Testing Processor Voltage Fluctuations

Rapid current changes (large di/dt) can lead to significant power supply voltage droops and timing errors in modern microprocessors. To test a processor's resilience to such errors and determine appropriate operating conditions, engineers generally create manual di/dt stressmarks that have large current variations at close to the power distribution network's resonance frequency to induce large voltage droops. This process is time-consuming and might need to be repeated several times to generate appropriate stressmarks for different system conditions (for example, different frequencies or di/dt throttling mechanisms). Furthermore, generating efficient di/dt stressmarks for multicore processors is difficult because of their complexity and synchronization issues. In this article, the authors measure and analyze di/dt issues on state-of-the-art multicore x86 systems. They present an automated di/dt stressmark generation framework called Audit to generate di/dt stressmarks quickly and effectively for multicore systems.