Resolve the GCE machine type at startup, not in a handler - #44
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gce_machine_type in crates/walgit-server/src/instance.rs forked curl inside a OnceLock::get_or_init, and info() reaches it from every readiness and health handler and the UI footer, so the first such request on an SSD host held a tokio worker for up to 300 ms on a subprocess. That is the tell principle VI names, a Command::new(...).output() on the async runtime. The probe is now a reqwest GET of the same URL with the same header, timeout and parsing, awaited once in serve() before the listener accepts, and only on the host that calls itself ssd (WALGIT_INSTANCE_KIND=ssd, or maintenance.disk = "ssd" with no explicit kind), which is the one shape whose info() prints a machine type and the only place the old code probed. Handlers now read the cell and nothing else; when the probe never ran, info() falls back to the cpu and memory shape exactly as it did when curl failed. Checked with cargo clippy -p walgit-server --all-targets --no-deps -- -D warnings, cargo test -p walgit-server --lib (the new test asserts a non-SSD host caches nothing and touches no network), cargo test -p walgit-server --test drain and cargo fmt --all -- --check. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01CSbhRh6UEjFrgBYYzucvDe
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gce_machine_type()incrates/walgit-server/src/instance.rsforkedcurlinside aOnceLock::get_or_init, andinstance::info()reaches it from every readiness and health handler (health.rslines 29, 36 and 42) and the UI footer, so the first such request on an SSD host held a tokio worker for up to 300 ms on a subprocess. That's the tell principle VI names: aCommand::new(...).output()on the async runtime.The probe is now a
reqwestGET of the same URL with the same header, 300 ms budget and parsing, awaited once inserve()before the listener accepts, and only on the host that calls itselfssd(WALGIT_INSTANCE_KIND=ssd, ormaintenance.disk = "ssd"with no explicit kind), which is the one shape whoseinfo()prints a machine type and the only place the old code probed. Handlers now read the cell and nothing else; when the probe never ran,info()falls back to the cpu and memory shape exactly as it did when curl failed. One unit test asserts a non-SSD host caches nothing and touches no network.Checked with
cargo clippy -p walgit-server --all-targets --no-deps -- -D warnings,cargo test -p walgit-server --lib(72 pass),cargo test -p walgit-server --test drain --test api_v1andcargo fmt --all -- --check. Not exercised on a real GCE VM; the request is byte for byte what curl sent.