The author has been working on optimizing the NetBSD/amd64 virtual machine kernel boot time. With performance enhancements, the kernel can now boot in less than 15ms on a not-so-modern i5-7600K using QEMU 6.2 with the microvm machine type. The performance branch, available on GitHub, introduces features like Generic PVH boot, a new PV bus for hypervisors without PCI, MMIO-backed devices, performance fixes, pvclock using KVM timecounter, and a TSLOG framework for tracing performance. The author provides a kernel configuration and instructions for testing with QEMU on Linux or NetBSD using NVMM. Additionally, the kernel is compatible with a PVH branch of AWS's Firecracker, and the author offers a basic configuration for testing. Feedback is encouraged, and precompiled binaries are provided for those who want to try it without compiling.<p>[Performance Branch on GitHub](<a href="https://github.com/NetBSDfr/NetBSD-src/tree/perf">https://github.com/NetBSDfr/NetBSD-src/tree/perf</a>)<p>[Precompiled Kernel and Disk Image](<a href="https://imil.net/NetBSD/disk.img" rel="nofollow">https://imil.net/NetBSD/disk.img</a>)
Discussed couple of days ago here: <a href="https://news.ycombinator.com/item?id=39015036">https://news.ycombinator.com/item?id=39015036</a>