Benchmark: NEW VS CACHED - MeasureThat.net

Script Preparation code:

var tab = [];

function cached(){
	tab[0] = Math.random();
  	tab[1] = Math.random();
  	tab[2] = Math.random();
  	tab[3] = Math.random();
}

function neww(){
	return [
      Math.random(),
      Math.random(),
  	  Math.random(),
      Math.random()
    ];
}

Tests:

CACHED
for (var i = 0; i < 100; i++) { cached(); }
NEW
for (var i = 0; i < 100; i++) { neww(); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
CACHED
NEW

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is being tested, compared options, pros and cons of those approaches, library usage, special JavaScript features or syntax, and other considerations.

**Benchmark Definition**

The benchmark definition consists of two functions: `cached()` and `neww()`. Both functions return an array of four random numbers generated using the `Math.random()` function. The difference between the two functions lies in how they generate these arrays:

- `cached()`: This function uses a local array (`tab`) to store intermediate results, which are then returned as part of the final result.
- `neww()`: This function returns an array directly.

**Comparison Options**

The benchmark compares two approaches:

1.  **Caching**: The `cached()` function uses caching by storing intermediate results in a local array (`tab`). If used again with the same arguments, it can reuse these cached values instead of recalculating them.
2.  **No Caching**: The `neww()` function does not use caching; each call generates new random numbers without reusing any previous values.

**Pros and Cons**

-   **Caching (`cached()`)**:
    -   Pros:
        *   Faster execution: By reusing cached values, the function avoids redundant calculations.
        -   Memory efficiency: The cache array is only accessed once during initial setup; subsequent calls reuse this data.
    -   Cons:
        -   Memory usage: Although memory usage per call is minimal, it can accumulate if the benchmark runs multiple iterations.
        -   Complexity in test code: Caching might make the test code more complex to manage due to potential edge cases and variable access issues.

-   **No Caching (`neww()`)**:
    -   Pros:
        -   Simplicity in test code: Without caching, the function's logic is straightforward.
        -   No memory usage concerns: There's no risk of accumulating memory usage with repeated calls.
    -   Cons:
        -   Slower execution: Each call to `neww()` generates new random numbers without reusing cached values.

**Library Usage**

There are no external libraries explicitly used in the provided benchmark definition or test cases. However, the use of `Math.random()` implies that a default JavaScript library (typically included with browsers) is being utilized.

**Special JavaScript Features/Syntax**

-   **Arrow Functions**: The functions defined using `function neww(){...}` and `function cached(){...}` are examples of arrow function syntax in JavaScript. This allows for concise, memory-efficient function definitions without the need to declare a `function` keyword or define a closure (`var tab = [];`).

**Other Considerations**

-   **Browser-specific Variants**: Depending on the browser being tested, some optimizations might be available (e.g., caching) that are not applicable across all environments.
-   **Device Platform and Operating System Effects**: The benchmark results provided include device platform and operating system information, which can affect performance due to factors like hardware capabilities, browser optimization levels, and OS-specific algorithms.

**Alternatives**

Other alternatives for this type of microbenchmark could involve testing different:

1.  **Math library optimizations**: Implementing a custom random number generator or exploring optimized libraries like `crypto.getRandomValues()`.
2.  **Caching strategies**: Investigating caching techniques beyond simple arrays, such as memoization using objects or maps.
3.  **Function inlining and caching with V8**: Exploring if the V8 JavaScript engine would optimize the functions differently based on their implementation.

These alternatives could provide more detailed insights into performance optimization strategies for specific use cases or libraries.

Latest run results:

Run details: (Test run date: 2025 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.167 Safari/537.36

Browser/OS: Chrome 64 on Windows

View result in a separate tab

Test name	Executions per second
CACHED	7736.0 Ops/sec
NEW	11335.7 Ops/sec

Related benchmarks:

NEW VS CACHED (version: 1)

Comparing performance of: CACHED vs NEW

Created: 6 years ago by: Registered User

Jump to the latest result

CACHED

NEW

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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