Open Source Summit India 2026

Performance profiling in virtualized environments has traditionally required trade-offs between accuracy and overhead. Mediated PMU, a recent change to Linux's built-in KVM hypervisor, fundamentally changes this by providing guests direct access to hardware Performance Monitoring Units (PMUs).

This talk will:
- Explore the differences between the old and new approaches.
- Demonstrate a reduction in PMU virtualization overhead and improvement in profiling accuracy.
- Discuss the key trade-off: while guests gain direct hardware access, the host loses the ability to profile guest workloads through perf.

This talk is ideal for virtualization engineers, kernel developers, and anyone performing performance analysis in cloud or virtualized environments who needs accurate, low-overhead profiling data.