Add a benchmark for TypedArray with zero-copy extension

Author: EddiG

benchmark/msgpack-benchmark.js

@@ -3,13 +3,65 @@
 "use strict";
 require("ts-node/register");
 const Benchmark = require("benchmark");
-const fs = require("fs");
-const msgpack = require("../src");
+
+const msgpackEncode = require("..").encode;
+const msgpackDecode = require("..").decode;
+const ExtensionCodec = require("..").ExtensionCodec;
+
+const float32ArrayExtensionCodec = new ExtensionCodec();
+float32ArrayExtensionCodec.register({
+  type: 0x01,
+  encode: (object) => {
+    if (object instanceof Float32Array) {
+      return new Uint8Array(object.buffer, object.byteOffset, object.byteLength);
+    }
+    return null;
+  },
+  decode: (data) => {
+    const copy = new Uint8Array(data.byteLength);
+    copy.set(data);
+    return new Float32Array(copy.buffer);
+  },
+});
+
+const float32ArrayZeroCopyExtensionCodec = new ExtensionCodec();
+float32ArrayZeroCopyExtensionCodec.register({
+  type: 0x01,
+  encode: (object) => {
+    if (object instanceof Float32Array) {
+      return (pos) => {
+        const bpe = Float32Array.BYTES_PER_ELEMENT;
+        const padding = 1 + ((bpe - ((pos + 1) % bpe)) % bpe);
+        const data = new Uint8Array(object.buffer);
+        const result = new Uint8Array(padding + data.length);
+        result[0] = padding;
+        result.set(data, padding);
+        return result;
+      };
+    }
+    return null;
+  },
+  decode: (data) => {
+    const padding = data[0];
+    const bpe = Float32Array.BYTES_PER_ELEMENT;
+    const offset = data.byteOffset + padding;
+    const length = data.byteLength - padding;
+    return new Float32Array(data.buffer, offset, length / bpe);
+  },
+});
 
 const implementations = {
   "@msgpack/msgpack": {
-    encode: require("..").encode,
-    decode: require("..").decode,
+    encode: msgpackEncode,
+    decode: msgpackDecode,
+  },
+  "@msgpack/msgpack (Float32Array extension)": {
+    encode: (data) => msgpackEncode(data, { extensionCodec: float32ArrayExtensionCodec }),
+    decode: (data) => msgpackDecode(data, { extensionCodec: float32ArrayExtensionCodec }),
+  },
+  "@msgpack/msgpack (Float32Array with zero-copy extension)": {
+    encode: (data) => msgpackEncode(data, { extensionCodec: float32ArrayZeroCopyExtensionCodec }),
+    decode: (data) => msgpackDecode(data, { extensionCodec: float32ArrayZeroCopyExtensionCodec }),
   },
   "msgpack-lite": {
     encode: require("msgpack-lite").encode,
@@ -21,28 +73,52 @@ const implementations = {
   },
 };
 
-// exactly the same as:
-// https://raw.githubusercontent.com/endel/msgpack-benchmark/master/sample-large.json
-const sampleFiles = ["./sample-large.json"];
+const samples = [
+  {
+    // exactly the same as:
+    // https://raw.githubusercontent.com/endel/msgpack-benchmark/master/sample-large.json
+    name: "./sample-large.json",
+    data: require("./sample-large.json"),
+  },
+  {
+    name: "Large array of numbers",
+    data: [
+      {
+        position: new Array(1e3).fill(1.14),
+      },
+    ],
+  },
+  {
+    name: "Large Float32Array",
+    data: [
+      {
+        position: new Float32Array(1e3).fill(1.14),
+      },
+    ],
+  },
+];
 
 function validate(name, data, encoded) {
-  if (JSON.stringify(data) !== JSON.stringify(implementations[name].decode(encoded))) {
-    throw new Error("Bad implementation: " + name);
-  }
+  return JSON.stringify(data) === JSON.stringify(implementations[name].decode(encoded));
 }
 
-for (const sampleFile of sampleFiles) {
-  const data = require(sampleFile);
+for (const sample of samples) {
+  const { name: sampleName, data } = sample;
   const encodeSuite = new Benchmark.Suite();
   const decodeSuite = new Benchmark.Suite();
 
   console.log("");
-  console.log("**" + sampleFile + ":** (" + JSON.stringify(data).length + " bytes in JSON)");
+  console.log("**" + sampleName + ":** (" + JSON.stringify(data).length + " bytes in JSON)");
   console.log("");
 
   for (const name of Object.keys(implementations)) {
     implementations[name].toDecode = implementations[name].encode(data);
-    validate(name, data, implementations[name].toDecode);
+    if (!validate(name, data, implementations[name].toDecode)) {
+      console.log("```");
+      console.log("Not supported by " + name);
+      console.log("```");
+      continue;
+    }
     encodeSuite.add("(encode) " + name, () => {
       implementations[name].encode(data);
     });
@@ -60,7 +136,7 @@ for (const sampleFile of sampleFiles) {
 
   console.log("");
 
-  decodeSuite.on("cycle", function(event) {
+  decodeSuite.on("cycle", (event) => {
     console.log(String(event.target));
   });