Separates what a VM IS (durable intent + identity + deterministic
derived paths — `VMRuntime`) from what is CURRENTLY TRUE about it
(firecracker PID, tap device, loop devices, dm-snapshot target — new
`VMHandles`). The durable state lives in the SQLite `vms` row; the
transient state lives in an in-memory cache on the daemon plus a
per-VM `handles.json` scratch file inside VMDir, rebuilt at startup
from OS inspection. Nothing kernel-level rides the SQLite schema
anymore.
Why:
Persisting ephemeral process handles to SQLite forced reconcile to
treat "running with a stale PID" as a first-class case and mix it
with real state transitions. The schema described what we last
observed, not what the VM is. Every time the observation model
shifted (tap pool, DM naming, pgrep fallback) the reconcile logic
grew a new branch. Splitting lets each layer own what it's good at:
durable records describe intent, in-memory cache + scratch file
describe momentary reality.
Shape:
- `model.VMHandles` = PID, TapDevice, BaseLoop, COWLoop, DMName,
DMDev. Never in SQLite.
- `VMRuntime` keeps: State, GuestIP, APISockPath, VSockPath,
VSockCID, LogPath, MetricsPath, DNSName, VMDir, SystemOverlay,
WorkDiskPath, LastError. All durable or deterministic.
- `handleCache` on `*Daemon` — mutex-guarded map + scratch-file
plumbing (`writeHandlesFile` / `readHandlesFile` /
`rediscoverHandles`). See `internal/daemon/vm_handles.go`.
- `d.vmAlive(vm)` replaces the 20+ inline
`vm.State==Running && ProcessRunning(vm.Runtime.PID, apiSock)`
spreads. Single source of truth for liveness.
- Startup reconcile: per running VM, load the scratch file, pgrep
the api sock, either keep (cache seeded from scratch) or demote
to stopped (scratch handles passed to cleanupRuntime first so DM
/ loops / tap actually get torn down).
Verification:
- `go test ./...` green.
- Live: `banger vm run --name handles-test -- cat /etc/hostname`
starts; `handles.json` appears in VMDir with the expected PID,
tap, loops, DM.
- `kill -9 $(pgrep bangerd)` while the VM is running, re-invoke the
CLI, daemon auto-starts, reconcile recognises the VM as alive,
`banger vm ssh` still connects, `banger vm delete` cleans up.
Tests added:
- vm_handles_test.go: scratch-file roundtrip, missing/corrupt file
behaviour, cache concurrency, rediscoverHandles prefers pgrep
over scratch, returns scratch contents even when process is
dead (so cleanup can tear down kernel state).
- vm_test.go: reconcile test rewritten to exercise the new flow
(write scratch → reconcile reads it → verifies process is gone →
issues dmsetup/losetup teardown).
ARCHITECTURE.md updated; `handles` added to Daemon field docs.
Beat VM create wall time without changing VM semantics.
Generate a work-seed ext4 sidecar during image builds and rootfs rebuilds, then clone and resize that seed for each new VM instead of rebuilding /root from scratch. Plumb the new seed artifact through config, runtime metadata, store state, runtime-bundle defaults, doctor checks, and default-image reconciliation so older images still fall back cleanly.
Add a daemon TAP pool to keep idle bridge-attached devices warm, expose stage timing in lifecycle logs, add a create/SSH benchmark script plus Make target, and teach verify.sh that tap-pool-* devices are reusable capacity rather than cleanup leaks.
Validated with go test ./..., make build, ./verify.sh, and make bench-create ARGS="--runs 2".
VM start, image build, and network/setup failures were hard to diagnose because bangerd emitted almost no lifecycle logs and the Firecracker SDK logger was discarded. This adds a daemon-wide JSON logger with configurable log level so failures leave breadcrumbs instead of only side effects.
Log the main daemon and VM lifecycle stages, preserve raw Firecracker and image-build helper output in dedicated files, and include those log paths in daemon status and returned errors. Bridge SDK logrus output into the daemon logger at debug level so low-level Firecracker diagnostics are available without making normal info logs unreadable.
Validation: go test ./... and make build. Left unrelated worktree changes out of this commit, including internal/api/types.go, the deleted shell scripts, and my-rootfs.ext4.
