Benchmark: test for loop for onlyoffice performance

Script Preparation code:

var array = new Array(65535).fill(0);
var q = 0;

Tests:

for i
for (var i = 0; i < array.length; i++) { q = array[i]; }
for i no count length
for (var i = 0, c = array.length; i < c; i++) { q = array[i]; }
for i no count length ++i
for (var i = 0, c = array.length; i < c; ++i) { q = array[i]; }
for of
for (var i of array) { q = i; }
forEach =>
array.forEach((i) => q = i);
forEach no =>
array.forEach(function(i){ q = i; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for i
for i no count length
for i no count length ++i
for of
forEach =>
forEach no =>

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.6.1 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
for i	47169.0 Ops/sec
for i no count length	46574.0 Ops/sec
for i no count length ++i	46684.2 Ops/sec
for of	10964.9 Ops/sec
forEach =>	2588.9 Ops/sec
forEach no =>	1678.5 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Measuring JavaScript performance is a fascinating topic.

**What's being tested?**

The provided benchmark measures the performance of different `for` loop constructs in JavaScript, specifically:

1. Traditional `for` loops with explicit counter variables (`i`)
2. `for` loops without counting the length of the array directly
3. Incremental `for` loops using the `++` operator
4. Array iteration using the `forEach()` method with and without the arrow function syntax

**Options comparison**

The benchmark compares six different approaches:

1. **Traditional `for` loop**: This is a straightforward, explicit counter variable-based approach.
2. **No count length**: This approach avoids direct array length calculation, relying on the length property of the array object.
3. **Incremental `for` loop**: Similar to traditional loops but uses the `++` operator for incrementing the counter.
4. **`forEach()` with arrow function**: Uses the modern `forEach()` method with the arrow function syntax (`(i) => q = i;`) for iteration.
5. **`forEach()` without arrow function**: Uses the older `forEach()` method with a traditional function declaration (`function(i){ ... }`).
6. **For of loop**: Utilizes the new "for...of" loop syntax (introduced in ECMAScript 2015) for iterating over arrays.

**Pros and Cons**

Here's a brief summary:

* **Traditional `for` loop**:
	+ Pros: Easy to read, understand, and maintain.
	+ Cons: Can be slower due to explicit counter management.
* **No count length**:
	+ Pros: Reduces unnecessary calculations and potential aliasing issues.
	+ Cons: May require more complex logic for conditional statements or array indexing.
* **Incremental `for` loop**:
	+ Pros: Can optimize iteration by avoiding unnecessary array lookups.
	+ Cons: Requires careful handling of the counter variable's increment.
* **`forEach()` with arrow function**:
	+ Pros: Modern, concise syntax with minimal boilerplate code.
	+ Cons: May have performance implications due to the arrow function's call overhead.
* **`forEach()` without arrow function**:
	+ Pros: Wide compatibility across older browsers and environments.
	+ Cons: Less modern and more verbose than the arrow function version.
* **For of loop**:
	+ Pros: Elegant, expressive syntax with improved iteration support.
	+ Cons: Limited browser support for newer versions.

**Library usage**

The benchmark uses none explicitly. The `array` object is a built-in JavaScript data structure.

**Special JS features or syntax**

This benchmark highlights the use of:

1. **Arrow function syntax**: Introduced in ECMAScript 2015, this syntax provides concise and readable code for simple functions.
2. **For...of loop syntax**: Also introduced in ECMAScript 2015, this syntax offers a more expressive way to iterate over arrays.

**Alternatives**

If you're interested in exploring alternative approaches or optimizing JavaScript performance:

1. **Safari's WebKit engine**: Offers some unique optimizations for JavaScript execution.
2. **SpiderMonkey engine (Firefox)**: Provides various tuning options and profiling tools for fine-tuning JavaScript performance.
3. **V8 engine (Chrome)**: A popular, high-performance JavaScript engine with many optimization features.

These alternatives might be worth exploring if you're working on a project that requires intense JavaScript performance optimization.

Related benchmarks:

test for loop for onlyoffice performance (version: 0)

Test different for loops

Comparing performance of: for i vs for i no count length vs for i no count length ++i vs for of vs forEach => vs forEach no =>

Created: 3 years ago by: Guest

Jump to the latest result

for i

for i no count length

for i no count length ++i

for of

forEach =>

forEach no =>

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):