High Frequency Performance Monitoring via Architectural Event Measurement

Abstract

Obtaining detailed software execution information via hardware performance counters is a powerful analysis technique. The performance counters provide an effective method to monitor program behaviors; hence performance bottlenecks due to hardware architecture or software design and implementation can be identified, isolated and improved on. The granularity and overhead of the monitoring mechanism, however, are paramount to proper analysis. Many prior designs have been able to provide performance counter monitoring with inherited drawbacks such as intrusive code changes, a slow timer system, or the need for a kernel patch. In this paper, we present K-LEB (Kernel - Lineage of Event Behavior), a new monitoring mechanism that can produce precise, non-intrusive, low overhead, periodic performance counter data using a kernel module based design. Our proposed approach has been evaluated on three different case studies to demonstrate its effectiveness, correctness and efficiency. By moving the responsibility of timing to kernel space, K-LEB can gather periodic data at a 100μs rate, which is 100 times faster than other comparable performance counter monitoring approaches. At the same time, it reduces the monitoring overhead by at least 58.8%, and the difference between the recorded performance counter readings and those of other tools are less than 0.3%.