Benchmarking

This guide walks through the benchmarking tooling in Syn_OS: a lightweight in-daemon health check for everyday users, a full system baseline collector for admins and release engineers, and Criterion micro-benchmarks for contributors.

Overview

Layer	Who it’s for	When it runs	Where results go
Lite benchmark (in-daemon)	End users	Periodically, inside synos-daemon	/var/lib/synos/benchmark-lite.json
System baseline (benchmark-baseline.sh)	Admins / release engineers	Manual + first ISO boot	/var/lib/synos/benchmark-baseline-*.txt
Criterion micro-benchmarks	Developers	cargo bench	target/criterion/ (HTML reports)

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1 — Lite Benchmark (End-User)

The lite benchmark runs automatically inside synos-daemon and collects two low-overhead metrics:

• Available memory (from /proc/meminfo)
• IPC socket bind latency (create + close a Unix datagram socket)

View the latest result

cat /var/lib/synos/benchmark-lite.json

{
  "collected_at": "uptime:42.37",
  "mem_available_mib": 5210,
  "mem_total_mib": 7939,
  "socket_bind_us": 42,
  "memory_status": "ok"
}

memory_status	Meaning
ok	≥ 20% of total RAM available
low	5–19% available — consider closing applications
critical	< 5% available — system may become unresponsive

Adjust or disable

/etc/synos/synos-daemon.toml

[benchmark]
enabled = true
interval_secs = 300   # minimum 60
output_path = "/var/lib/synos/benchmark-lite.json"  # "" = log-only

sudo systemctl restart synos-daemon

Read results from the system log

journalctl -u synos-daemon -f | grep lite-bench

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2 — System Baseline (benchmark-baseline.sh)

Captures a Markdown report suitable for comparing across installs, updates, and hardware.

# From the Syn_OS repository root:
./benchmark-baseline.sh

# Or on any installed system:
bash /usr/share/synos/scripts/benchmark-baseline.sh

# With options
./benchmark-baseline.sh --output-dir /tmp/my-benchmarks --iterations 10

Output lands in reports/benchmark-baseline-<YYYYMMDD-HHmmss>.txt.

What’s measured

Section	Data collected
Memory Footprint	Total, used, available, buffers, cached (MiB)
Boot Time	systemd-analyze, with /proc/uptime fallback
Daemon Startup Latency	Time to first log line, N samples (min/max/mean)
Running Services	systemctl snapshot of relevant units

On a fresh install, the Calamares post-installer automatically captures a baseline on first boot — this becomes the reference point for future comparisons on that hardware.

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3 — Criterion Micro-Benchmarks (Developers)

Exercises hot paths in synos-daemon with the Criterion framework — statistical noise rejection, warm-up runs, HTML reports.

cargo bench -p synos-daemon
# or, via the justfile:
just bench

Benchmark	What it measures
quest_toml_parse_single	TOML parse latency for one quest file
quest_validation_valid / quest_validation_reject	Validation throughput
quest_batch_load/1 … /100	Full scan → parse → validate for N files
unix_socket_bind	Unix datagram socket bind + drop latency

View the HTML report:

xdg-open target/criterion/report/index.html

Criterion flags a regression when the new mean falls statistically outside the confidence interval of the previous run.

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4 — Quick Reference

cat /var/lib/synos/benchmark-lite.json          # latest lite benchmark
journalctl -u synos-daemon -f | grep lite-bench # follow live daemon log
./benchmark-baseline.sh                         # full system baseline
just bench-lite                                 # lite benchmark, developer shortcut
just bench                                      # Criterion micro-benchmarks
ls -lt reports/benchmark-baseline-*.txt         # list past reports

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5 — Troubleshooting

Lite benchmark not writing output

1. Check benchmark.enabled = true in /etc/synos/synos-daemon.toml.
2. Verify the output directory is writable: ls -la /var/lib/synos/
3. Check daemon logs: journalctl -u synos-daemon --since "5 min ago"

benchmark-baseline.sh shows “binary not found”

cargo build --release -p synos-daemon
./benchmark-baseline.sh

Criterion benchmarks fail to compile

synos-daemon needs systemd headers, installed via pacman:

sudo pacman -S systemd-libs
cargo bench -p synos-daemon

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6 — For ISO Builders

The baseline script is wired into the Calamares post-install sequence and runs as root on first boot of a freshly installed Master ISO. To bundle it into a custom ISO rootfs:

install -m 755 benchmark-baseline.sh \
  "${ROOTFS}/usr/share/synos/scripts/benchmark-baseline.sh"