bench: backport main's benchmarks to release for before/after runs

js/json/bench/codec.ts

@@ -0,0 +1,34 @@
+/** Sweep snapshot codec cost over document size and changed keys. */
+import { Decoder } from "../src/snapshot/decoder.ts";
+import { Encoder } from "../src/snapshot/encoder.ts";
+
+const updates = 256;
+console.log("keys\tchanged\tcompression\tms/update");
+for (const keys of [1, 10, 100, 1000]) {
+	for (const changed of new Set([1, Math.min(10, keys)])) {
+		for (const compression of ["none", "deflate"] as const) {
+			const samples: number[] = [];
+			for (let sample = 0; sample < 3; sample++) {
+				const config = { deltaRatio: 100, compression };
+				const encoder = new Encoder<Record<string, number>>(config);
+				const decoder = new Decoder<Record<string, number>>(config);
+				let value = Object.fromEntries(Array.from({ length: keys }, (_, n) => [`k${n}`, 0]));
+				const start = performance.now();
+				for (let n = 1; n <= updates; n++) {
+					value = { ...value };
+					for (let key = 0; key < changed; key++) value[`k${key}`] = n;
+					const frame = encoder.update(value);
+					if (frame) {
+						if (frame.keyframe) decoder.snapshot(frame.payload);
+						else decoder.delta(frame.payload);
+						frame.commit();
+					}
+					if (decoder.decode()?.k0 !== n) throw new Error("codec benchmark lost an update");
+				}
+				samples.push((performance.now() - start) / updates);
+			}
+			samples.sort((a, b) => a - b);
+			console.log(`${keys}\t${changed}\t${compression}\t${samples[1]?.toFixed(6)}`);
+		}
+	}
+}

js/justfile

@@ -48,6 +48,11 @@ bench name:
     bun install --frozen-lockfile
     bun net/bench/{{ name }}.ts
 
+# Time Effect create and close, which pays for the creation stack its diagnostics print.
+signals-bench:
+    bun install --frozen-lockfile
+    bun signals/bench/effect.ts
+
 # Build all packages.
 build:
     bun run --filter='*' build

js/net/bench/frames.ts

@@ -13,6 +13,9 @@ import * as Path from "../src/path.ts";
 import { Reader, Stream } from "../src/stream.ts";
 import * as Varint from "../src/varint.ts";
 
+// Keep protocol diagnostics out of the measured CSV on stdout.
+console.debug = console.error;
+
 const frameSizes = [16, 100, 1000];
 const chunkSizes = [1200, 16 * 1024, 64 * 1024];
 const framesPerGroup = 50;

js/signals/bench/effect.ts

@@ -0,0 +1,59 @@
+/** Time creating and closing an Effect, bare and with a tracked signal, against a bare `new Error()`. */
+import { Effect, Signal } from "../src/index.ts";
+
+const runs = 20_000;
+const reps = 9;
+const signal = new Signal(0);
+let checksum = 0;
+let tracked = 0;
+
+const ops: [string, () => void | Promise<void>][] = [
+	// The creation stack each Effect captures for its diagnostics; the floor for the rows below.
+	[
+		"new-error",
+		() => {
+			checksum += new Error("created here:").message.length;
+		},
+	],
+	[
+		"create-close",
+		() => {
+			new Effect().close();
+			checksum++;
+		},
+	],
+	[
+		"create-get-close",
+		async () => {
+			const effect = new Effect((effect) => {
+				tracked += effect.get(signal) + 1;
+			});
+			// The callback runs in a microtask, so yield once to let it track the signal before closing.
+			await Promise.resolve();
+			effect.close();
+		},
+	],
+];
+
+// Nanoseconds per op for the fastest of several reps, since a slower one measured the machine.
+async function time(body: () => void | Promise<void>): Promise<number> {
+	let best = Number.POSITIVE_INFINITY;
+	for (let rep = 0; rep < reps; rep++) {
+		const start = performance.now();
+		for (let i = 0; i < runs; i++) {
+			// Awaiting a sync row would add a microtask hop it doesn't pay.
+			const pending = body();
+			if (pending instanceof Promise) await pending;
+		}
+		best = Math.min(best, ((performance.now() - start) * 1e6) / runs);
+	}
+	return best;
+}
+
+// Time every op once first and discard it, so the JIT has seen all of them and the first row isn't timing warmup.
+for (const [, body] of ops) await time(body);
+
+console.log("op,ns_per_op");
+for (const [op, body] of ops) console.log(`${op},${(await time(body)).toFixed(0)}`);
+if (checksum === 0) throw new Error("benchmark did no work");
+if (tracked === 0) throw new Error("create-get-close never ran its effect");

rs/kio/Cargo.toml

@@ -39,5 +39,9 @@ harness = false
 name = "channel"
 harness = false
 
+[[bench]]
+name = "contended"
+harness = false
+
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ['cfg(loom)'] }