The pace and volume of code churn necessary to evolve modern software systems present challenges for analyzing the performance impact of any set of code changes. Traditional methods used in performance analysis rely on extensive data collection and profiling, which often takes days. For large organizations utilizing Continuous Integration (CI) and Continuous Deployment (CD), these traditional techniques often fail to provide timely and actionable data. A different impact analysis method that allows for more efficient detection of performance regressions is needed. We propose the utilization of user mode memory allocator churn as a novel approach to performance engineering. User mode allocator churn acts as a proxy metric to evaluate the relative change in the cost of specific tasks. We prototyped the memory allocation churn methodology while engaged in performance engineering for a major iOS application. We find that calculating and analyzing memory allocator churn (a) results in deterministic measurements, (b) is efficient for determining the presence of both individual performance regressions and general performance-related trends, and (c) is a suitable alternative to measuring the task completion time.