This document describes virtPerf, a tool for profiling application performance and resource utilization in virtualized environments. virtPerf can generate workload, configure VM resources, and measure performance metrics and resource usage. It was built on AutoPerf to address limitations of existing tools in virtualized settings. The document outlines virtPerf's architecture and capabilities for workload control, VM configuration, profiling under migration and interference. It also presents experimental results using virtPerf with multi-tier applications to analyze effects of resource allocation, VM placement, and migration on performance. Future work areas are identified like adding more workload and profiling features to virtPerf.