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encodeInto with subarrays vs offsets (https://jsbench.github.io/#f7ee4cec9df6f49e404d44ca8d5d3de8) #jsbench #jsperf
Raw
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<title>encodeInto with subarrays vs offsets</title>
<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
<script src="./suite.js"></script>
</head>
<body>
<h1>Open the console to view the results</h1>
<h2><code>cmd + alt + j</code> or <code>ctrl + alt + j</code></h2>
</body>
</html>
Raw
suite.js
"use strict";
(function (factory) {
if (typeof Benchmark !== "undefined") {
factory(Benchmark);
} else {
factory(require("benchmark"));
}
})(function (Benchmark) {
var suite = new Benchmark.Suite;
Benchmark.prototype.setup = function () {
// Change these to adjust how many subarray we'll make
const LEN = 10_000;
const MUL = 4;
console.assert(LEN % MUL === 0);
// - - - - -
const readBytes = MUL * 3;
const writeBytes = MUL * 5;
const data = "xx€".repeat(LEN);
const output = new Uint8Array(5 * LEN);
const subarrays = new Array(LEN / MUL);
const encoder = new TextEncoder();
for (let i = 0; i < subarrays.length; i++) {
subarrays[i] = output.subarray(i * writeBytes, (i + 1) * writeBytes);
}
function encodeInto(input, readStart, readEnd, into, writeStart) {
let i = readStart;
let j = writeStart;
while (i < readEnd) {
let c = input.charCodeAt(i++);
if (c < 0x80) {
into[j++] = c;
} else if (c < 0x800) {
into[j++] = 0b1100_0000 | (c >> 6);
into[j++] = 0b1000_0000 | (c >> 0b0011_1111);
} else if (c < 0xd800 || c >= 0xe000) {
into[j++] = 0b1110_0000 | (c >> 12);
into[j++] = 0b1000_0000 | ((c >> 6) & 0b0011_1111);
into[j++] = 0b1000_0000 | (c & 0b0011_1111);
} else {
const c2 = input.charCodeAt(i++);
c = 0x10000 + (((c & 0x3ff) << 10) | (c2 & 0x3ff));
into[j++] = 0b1111_0000 | (c >> 18);
into[j++] = 0b1000_0000 | ((c >> 12) & 0b0011_1111);
into[j++] = 0b1000_0000 | ((c >> 6) & 0b0011_1111);
into[j++] = 0b1000_0000 | (c & 0b0011_1111);
}
}
return { read: i - readStart, written: j - writeStart };
}
};
suite.add("TextEncoder (on-the-fly subarrays)", function () {
// TextEncoder (on-the-fly subarrays)
for (let read = 0, written = 0; read < data.length; ) {
const stats = encoder.encodeInto(
data.substring(read, read + readBytes),
output.subarray(written, written + writeBytes),
);
read += stats.read;
written += stats.written;
}
});
suite.add("TextEncoder (premade subarrays)", function () {
// TextEncoder (premade subarrays)
for (let read = 0, w = 0; read < data.length; w++) {
const stats = encoder.encodeInto(
data.substring(read, read + readBytes),
subarrays[w],
);
read += stats.read;
}
});
suite.add("custom encodeInto (on-the-fly subarrays, substrings)", function () {
// custom encodeInto (on-the-fly subarrays, substrings)
for (let read = 0, written = 0; read < data.length; ) {
const stats = encodeInto(
data.substring(read, read + readBytes),
0,
readBytes,
output.subarray(written, written + writeBytes),
0,
);
read += stats.read;
written += stats.written;
}
});
suite.add("custom encodeInto (premade subarrays, substrings)", function () {
// custom encodeInto (premade subarrays, substrings)
for (let read = 0, w = 0; read < data.length; w++) {
const stats = encodeInto(
data.substring(read, read + readBytes),
0,
readBytes,
subarrays[w],
0,
);
read += stats.read;
}
});
suite.add("custom encodeInto (write offset, substrings)", function () {
// custom encodeInto (write offset, substrings)
for (let read = 0, written = 0; read < data.length; ) {
const stats = encodeInto(
data.substring(read, read + readBytes),
0,
readBytes,
output,
written,
);
read += stats.read;
written += stats.written;
}
});
suite.add("custom encodeInto (on-the-fly subarrays, read offset)", function () {
// custom encodeInto (on-the-fly subarrays, read offset)
for (let read = 0, written = 0; read < data.length; ) {
const stats = encodeInto(
data,
read,
read + readBytes,
output.subarray(written, written + writeBytes),
0,
);
read += stats.read;
written += stats.written;
}
});
suite.add("custom encodeInto (premade subarrays, read offset)", function () {
// custom encodeInto (premade subarrays, read offset)
for (let read = 0, w = 0; read < data.length; w++) {
const stats = encodeInto(
data,
read,
read + readBytes,
subarrays[w],
0,
);
read += stats.read;
}
});
suite.add("custom encodeInto (write offset, read offset)", function () {
// custom encodeInto (write offset, read offset)
for (let read = 0, written = 0; read < data.length; ) {
const stats = encodeInto(
data,
read,
read + readBytes,
output,
written,
);
read += stats.read;
written += stats.written;
}
});
suite.on("cycle", function (evt) {
console.log(" - " + evt.target);
});
suite.on("complete", function (evt) {
console.log(new Array(30).join("-"));
var results = evt.currentTarget.sort(function (a, b) {
return b.hz - a.hz;
});
results.forEach(function (item) {
console.log((idx + 1) + ". " + item);
});
});
console.log("encodeInto with subarrays vs offsets");
console.log(new Array(30).join("-"));
suite.run();
});
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