Hasty Briefsbeta

Profiling tools I use for QEMU storage performance optimization

15 days ago
  • #KVM
  • #Performance Analysis
  • #QEMU
  • The author discusses tools for analyzing storage performance in QEMU/KVM environments.
  • Performance analysis is challenging without clear bottlenecks; measuring multiple system layers helps identify issues.
  • kvm_stat is highlighted for monitoring KVM events like vmentry/vmexit, MSR accesses, and interrupt injections.
  • sysstat tools (mpstat, pidstat, iostat) are recommended for monitoring CPU, process, and disk activity across guests and hosts.
  • blktrace and btt are suggested for analyzing block I/O activity and comparing guest vs. host I/O patterns.
  • perf-top is used for CPU profiling to identify hot functions and inefficiencies in QEMU and host kernel.
  • perf-trace provides system call monitoring, useful for identifying blocking calls or excessive invocations.
  • The post concludes by mentioning the bcc eBPF tools for advanced performance monitoring and invites reader feedback on preferred tools.