{
  "slug": "microvm-checkpoint-restore",
  "question": "How fast can a microVM Space checkpoint and restore?",
  "answer": "A microVM Space restored from a checkpoint to a ready Space in 611 ms (p50, n = 10), and checkpointing the running Space took 695.5 ms, on a Mac Studio (Apple M2 Max, 96 GB), measured 2026-10-25 on Cua Spaces 0.15.0.",
  "status": "measured",
  "url": "https://cua.ai/benchmarks/microvm-checkpoint-restore",
  "csv": "https://cua.ai/benchmarks/microvm-checkpoint-restore.csv",
  "markdown": "https://cua.ai/benchmarks/microvm-checkpoint-restore.md",
  "group": "Fork and snapshot",
  "current": {
    "run": "2026-10-25",
    "schema": "cua.bench-result/v1",
    "bench": "microvm-fork.vz",
    "slug": "microvm-checkpoint-restore",
    "metric": "restore_ms",
    "value": 611,
    "unit": "ms",
    "stat": "p50",
    "n": 10,
    "percentiles": {
      "p50": 611,
      "p90": 617,
      "p95": 618,
      "p99": 618,
      "min": 607,
      "max": 618
    },
    "extra": {
      "checkpoint_ms_p50": 695.5,
      "checkpoint_ms_p95": 699.5,
      "fork_running_ms_p50": 1214.5,
      "fork_running_ms_p95": 1237.8,
      "fanout8_wall_ms": 1539,
      "fanout8_each_p50_ms": 1463.5,
      "memory_host_delta_per_fork_mib": 1927,
      "guest_used_mib": 295
    },
    "samples_csv": "samples.csv",
    "measured_at": "2026-10-25T01:19:40Z",
    "build": {
      "cua": "0.9.0",
      "cua_spacesd": "0.8.0",
      "app": "0.15.0",
      "source": "Cua Spaces 0.15.0 DMG (https://github.com/trycua/cua/releases/download/cua-spaces-v0.15.0/cua-spaces-0.15.0-darwin-universal.dmg, sha256 8725a09ba4132aa8a1667fa48c86416c91d5dec0d3c7dc93f88f5f3e29e0aba0): bundled cua 0.9.0, Helpers/cua-spacesd 0.8.0, cua-vz",
      "published": true,
      "harness": "built from tag cua-spaces-v0.15.0 (709b18d9ee) on the host: cargo build --release -p cua-sdk --example rollout_bench --example channel_bench (Rust 1.97.1)"
    },
    "host": {
      "name": "Mac Studio",
      "model": "Mac14,13 (Mac Studio)",
      "chip": "Apple M2 Max",
      "cpus": 12,
      "memory_gb": 96,
      "os": "macOS 26.6.2 (25G83)",
      "where": "local"
    },
    "environment": {
      "load_avg_before": [
        1.35,
        2.74,
        6.7
      ],
      "other_vms": 1,
      "network": "n/a (local)",
      "kind": "microvm",
      "image": "ghcr.io/trycua/linux:24.04-slim",
      "shape": "2 vCPU, 2 GiB (runtime vz)"
    },
    "method": "Driver on the host: `bench/microvm-fork/bench.sh` from tag cua-spaces-v0.15.0 with N=10, FANOUT=8, through the release's `cua` CLI and daemon. Source: a microVM Space (`--kind microvm`, runtime vz via the bundled cua-vz, 2 vCPU / 2 GiB) that wrote 256 MiB to /dev/shm. Timed (wall time of each CLI command; create/fork return once the Space's cua-spacesd answers with its own token): checkpoint = `cua sb checkpoint` of the running source (n=10); restore = `cua sb fork <checkpoint>` to a ready Space (n=10, serial, each deleted); fork_running = `cua sb fork <running Space>` (n=10); fan-out = 8 forks of one checkpoint at once (wall). Headline = restore p50.",
    "reproduce": "# On an Apple silicon Mac (macOS 26), with Rust (rustup) and git:\ncurl -fLO https://github.com/trycua/cua/releases/download/cua-spaces-v0.15.0/cua-spaces-0.15.0-darwin-universal.dmg\nhdiutil attach -nobrowse -mountpoint /tmp/cua-dmg cua-spaces-0.15.0-darwin-universal.dmg\nmkdir -p ~/bench && ditto \"/tmp/cua-dmg/Cua Spaces.app\" ~/bench/\"Cua Spaces.app\" && hdiutil detach /tmp/cua-dmg\ngit clone --depth 1 --branch cua-spaces-v0.15.0 https://github.com/trycua/cua ~/bench/cua\n(cd ~/bench/cua/libs/cua && cargo build --locked --release -p cua-sdk --example rollout_bench --example channel_bench)\nexport PATH=\"$HOME/bench/Cua Spaces.app/Contents/MacOS:$PATH\" CUA_HOME=~/bench/home DO_NOT_TRACK=1 CUA_TELEMETRY=0\nRB=~/bench/cua/libs/cua/target/release/examples/rollout_bench\ncua daemon start --foreground &\nCUA=cua OUT=results N=10 FANOUT=8 bash ~/bench/cua/libs/cua/bench/microvm-fork/bench.sh",
    "caveats": [
      "Host memory added per running fork in the fan-out was ~1,927 MiB (8 forks: +15,419 MiB) for a guest using 295 MiB: forks did not share the checkpoint's memory on this release.",
      "Times include the cua CLI process start (a few ms)."
    ],
    "sources": [],
    "status": "measured"
  },
  "earlier": []
}