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Speed up VM create with work seeds

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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".
This commit is contained in:
Thales Maciel 2026-03-18 21:22:12 -03:00
parent a14a80fd6b
commit c8d9a122f9
No known key found for this signature in database
GPG key ID: 33112E6833C34679
24 changed files with 695 additions and 44 deletions
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9
internal/config/config_test.go
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@ -20,6 +20,7 @@ func TestLoadDerivesArtifactPathsFromRuntimeDir(t *testing.T) {
VSockPingHelperPath: "bin/banger-vsock-pingd",
DefaultPackages: "config/packages.apt",
DefaultRootfs: "images/rootfs-docker.ext4",
DefaultWorkSeed: "images/rootfs-docker.work-seed.ext4",
DefaultKernel: "kernels/vmlinux",
DefaultInitrd: "kernels/initrd.img",
DefaultModulesDir: "modules/current",
@ -32,6 +33,7 @@ func TestLoadDerivesArtifactPathsFromRuntimeDir(t *testing.T) {
meta.VSockPingHelperPath,
meta.DefaultPackages,
meta.DefaultRootfs,
meta.DefaultWorkSeed,
meta.DefaultKernel,
meta.DefaultInitrd,
filepath.Join(meta.DefaultModulesDir, "modules.dep"),
@ -79,6 +81,9 @@ func TestLoadDerivesArtifactPathsFromRuntimeDir(t *testing.T) {
if cfg.DefaultRootfs != filepath.Join(runtimeDir, meta.DefaultRootfs) {
t.Fatalf("DefaultRootfs = %q", cfg.DefaultRootfs)
}
if cfg.DefaultWorkSeed != filepath.Join(runtimeDir, meta.DefaultWorkSeed) {
t.Fatalf("DefaultWorkSeed = %q", cfg.DefaultWorkSeed)
}
if cfg.DefaultBaseRootfs != filepath.Join(runtimeDir, meta.DefaultRootfs) {
t.Fatalf("DefaultBaseRootfs = %q", cfg.DefaultBaseRootfs)
}
@ -106,6 +111,7 @@ func TestLoadFallsBackToLegacyRuntimeLayoutWithoutBundleMetadata(t *testing.T) {
"banger-vsock-pingd",
"packages.apt",
"rootfs-docker.ext4",
"rootfs-docker.work-seed.ext4",
"wtf/root/boot/vmlinux-6.8.0-94-generic",
"wtf/root/boot/initrd.img-6.8.0-94-generic",
"wtf/root/lib/modules/6.8.0-94-generic/modules.dep",
@ -131,6 +137,9 @@ func TestLoadFallsBackToLegacyRuntimeLayoutWithoutBundleMetadata(t *testing.T) {
if cfg.VSockPingHelperPath != filepath.Join(runtimeDir, "banger-vsock-pingd") {
t.Fatalf("VSockPingHelperPath = %q", cfg.VSockPingHelperPath)
}
if cfg.DefaultWorkSeed != filepath.Join(runtimeDir, "rootfs-docker.work-seed.ext4") {
t.Fatalf("DefaultWorkSeed = %q", cfg.DefaultWorkSeed)
}
if cfg.DefaultKernel != filepath.Join(runtimeDir, "wtf/root/boot/vmlinux-6.8.0-94-generic") {
t.Fatalf("DefaultKernel = %q", cfg.DefaultKernel)
}