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https://github.com/mulgadc/spinifex.git
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joshsiv-mulga
a5efd45168
t1→t2 hypervisor: 3224 ms → 264 ms (12×). 128 MiB guest now boots
cleanly without OOM, reverting the temporary 512 MiB bump.
Root causes:
1. build-microvm-image.sh staged the entire chroot into the cpio
without dropping /boot, embedding a duplicate vmlinuz, Alpine's
stock initramfs-virt, System.map, and a "boot → ." symlink loop
(~25 MiB). Decompression peak exceeded 128 MiB. Strip /boot after
the kernel is copied out, before the cpio. Initramfs drops from
31 MiB → 11 MiB (53 MiB → 28 MiB uncompressed); total artifact
42 MiB → 22 MiB.
2. vm/lifecycle.go burned 3 s of fixed sleep on every direct-boot
launch: 2 s nbdkit pre-exec wait (no nbdkit on direct-boot) and
1 s post-fork settle (QEMU binds QMP within ~10 ms when there is
no firmware, ROM, or block layer). Both extracted to
directBoot-aware helpers — nbdkitPreExecWait collapses to 0, and
qemuStartSettleWait to 50 ms.
3. KernelCmdline only carried `console=ttyS0 virtio_mmio.device=…`.
Added boot-time perf flags: quiet loglevel=3 (silence printk over
115200-baud isa-serial), mitigations=off (KVM guest on trusted
host, single-tenant LB workload), tsc=reliable, no_timer_check,
reboot=t, i8042.{nopnp,noaux,nokbd} (microvm has no PS/2).
4. init.sh dropped modprobe virtio_mmio (built-in:
CONFIG_VIRTIO_MMIO=y) and tightened polling: fw_cfg/iface waits go
from 10 × 200 ms (up to 2 s) to 5 × 20 ms (up to 100 ms).
Phase 2 gates:
- t1→t2 ≤ 300 ms ✅ 264 ms / 281 ms
- artifact ≤ 50 MiB ✅ 22 MiB (gate already in build script)
- ELBv2 e2e green ✅ 32/33 (pre-existing client-VM failure,
unrelated to microvm path)