Benchmark: This site broken

Script Preparation code:

var array = [];
for (var i=0, t=10000; i<t; i++) {
    array.push(Math.round(Math.random() * t))
}
var t=0;

Tests:

for let
for (let i = 0; i < array.length; i++) { t += array[i]; }
for var
for (var i = 0; i < array.length; i++) { t += array[i]; }
for let cached
let len=array.length; for (let i = 0; i < len; i++) { t += array[i]; }
for let cached (const)
const len=array.length; for (let i = 0; i < len; i++) { t += array[i]; }
for var cached
var len=array.length; for (var i = 0; i < len; i++) { t += array[i]; }
forEach
array.forEach(function(v, i) { t += v; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for let
for var
for let cached
for let cached (const)
for var cached
forEach

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_4_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/15.4 Mobile/15E148 Safari/604.1

Browser/OS: Mobile Safari 15 on iOS 15.4.1

View result in a separate tab

Test name	Executions per second
for let	604.2 Ops/sec
for var	603.6 Ops/sec
for let cached	779.6 Ops/sec
for let cached (const)	818.5 Ops/sec
for var cached	790.5 Ops/sec
forEach	1101.9 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark data.

**Benchmark Purpose**

The benchmark measures the performance of different JavaScript iteration methods in executing a simple calculation on an array of numbers. The goal is to determine which method is the fastest.

**Iteration Methods Compared**

The benchmark compares six different iteration methods:

1. **for let**: A traditional `for` loop with the `let` keyword for variable declaration.
2. **for var**: A traditional `for` loop with the `var` keyword for variable declaration.
3. **for let cached (const)**: Similar to `for let`, but uses a constant variable declaration (`const`) instead of re-declaration on each iteration.
4. **forEach**: The `Array.prototype.forEach()` method, which calls a callback function once for each element in the array.

**Pros and Cons of Each Approach**

1. **for let**:
	* Pros: More modern syntax, no need to declare variable before use, better scoping.
	* Cons: May incur overhead due to re-declaration on each iteration.
2. **for var**:
	* Pros: Legacy syntax, widely supported by older browsers.
	* Cons: Outdated syntax, potential naming conflicts, and scope issues.
3. **for let cached (const)**:
	* Pros: Combines the benefits of modern syntax with a constant variable declaration for performance optimization.
	* Cons: May require careful consideration of when to use `const` vs `let`.
4. **forEach**:
	* Pros: Native method, optimized for iteration, and concise syntax.
	* Cons: May incur overhead due to callback function execution, and less control over iteration logic.

**Library Usage**

There is no explicit library usage mentioned in the benchmark definition or test cases.

**Special JavaScript Features or Syntax**

No special features or syntax are used beyond what's already described above. However, it's worth noting that `forEach` method uses a callback function, which may incur additional overhead compared to traditional loops.

**Alternative Benchmarks**

Other alternatives for benchmarking iteration performance could include:

* Using a more complex array operation (e.g., sorting, filtering)
* Incorporating concurrency or parallelization
* Comparing different JavaScript engines (e.g., V8, SpiderMonkey) or browsers
* Adding noise or variability to the benchmark inputs to simulate real-world usage

Related benchmarks:

This site broken (version: 0)

Comparing performance of: for let vs for var vs for let cached vs for let cached (const) vs for var cached vs forEach

Created: 2 years ago by: Registered User

Jump to the latest result

for let

for var

for let cached

for let cached (const)

for var cached

forEach

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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