Benchmark: large string comparison1

Script Preparation code:

let s1MB = "0123456789".repeat(1000*100);
var strings1MB = Array.from(Array(20)).map(o=>s1MB + String.fromCharCode(32+~~(Math.random()*96)))

let s2MB = "0123456789".repeat(1000*200);
var strings2MB = Array.from(Array(20)).map(o=>s2MB + String.fromCharCode(32+~~(Math.random()*96)))

let s10MB = "0123456789".repeat(1000*1000);
var strings10MB = Array.from(Array(20)).map(o=>s10MB + String.fromCharCode(32+~~(Math.random()*96)))
function compare(a, b) {
    const lenA = a.length;
    const lenB = b.length;
    const minLen = lenA < lenB ? lenA : lenB;
    var i = 0;
    for (; i < minLen; ++i) {
        const ca = a.charCodeAt(i);
        const cb = b.charCodeAt(i);
        if (ca > cb)
            return 1;
        else if (ca < cb)
            return -1;
    }
    if (lenA === lenB)
        return 0;
    return lenA > lenB ? 1 : -1;
};

Tests:

1MB string comparison
const s1 = strings1MB[~~(strings1MB.length*Math.random())]; const s2 = strings1MB[~~(strings1MB.length*Math.random())]; const b = s1 === s2;
2MB string comparison
const s1 = strings2MB[~~(strings2MB.length*Math.random())]; const s2 = strings2MB[~~(strings2MB.length*Math.random())]; const b = s1 === s2;
10MB string comparison
const s1 = strings10MB[~~(strings10MB.length*Math.random())]; const s2 = strings10MB[~~(strings10MB.length*Math.random())]; const b = s1 === s2;
1MB string comparison+
const s1 = strings1MB[~~(strings1MB.length*Math.random())]; const s2 = strings1MB[~~(strings1MB.length*Math.random())]; const b = compare(s1,s2);
2MB string comparison+
const s1 = strings2MB[~~(strings2MB.length*Math.random())]; const s2 = strings2MB[~~(strings2MB.length*Math.random())]; const b = compare(s1,s2);
10MB string comparison+
const s1 = strings10MB[~~(strings10MB.length*Math.random())]; const s2 = strings10MB[~~(strings10MB.length*Math.random())]; const b = compare(s1,s2);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
1MB string comparison
2MB string comparison
10MB string comparison
1MB string comparison+
2MB string comparison+
10MB string comparison+

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
1MB string comparison	452040.8 Ops/sec
2MB string comparison	52613.8 Ops/sec
10MB string comparison	2013.2 Ops/sec
1MB string comparison+	246.2 Ops/sec
2MB string comparison+	113.9 Ops/sec
10MB string comparison+	22.7 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll dive into explaining what's being tested on the provided JSON.

**Benchmark Definition**

The benchmark is designed to measure the performance of string comparison in JavaScript. The test creates large strings with varying lengths (1MB, 2MB, and 10MB) and compares them using two approaches:

1. **Simple equality check**: `const b = s1 === s2;`
2. **Custom comparison function**: `function compare(s1, s2) { ... }`

**Comparison Approaches**

There are four test cases that compare the performance of these two approaches.

### Simple Equality Check

This approach uses a simple equality check (`===`) to compare two strings. This method is easy to implement but can be slow due to the overhead of creating string objects and comparing their lengths.

Pros:

* Easy to understand and implement
* No need for custom libraries or dependencies

Cons:

* Can be slower than other methods due to overhead of creating string objects and comparing lengths

### Custom Comparison Function

This approach uses a custom comparison function (`compare`) to compare two strings. The function takes into account the length of each string and compares characters from left to right.

Pros:

* Can be faster than simple equality check by avoiding unnecessary operations
* Allows for more control over the comparison logic

Cons:

* Requires implementing a custom comparison function, which can add complexity
* May require additional dependencies or libraries

**Library Usage**

There is no explicit library usage mentioned in the benchmark definition. However, the `Array.from` method and `String.fromCharCode` are used to create large strings with random characters. These methods are part of the standard JavaScript API.

**Special JS Features/Syntax**

None of the test cases explicitly use any special JavaScript features or syntax. The code is straightforward and easy to understand.

**Device and Browser Variations**

The benchmark results show variations in performance across different devices (Desktop) and browsers (Chrome 123). This suggests that there may be platform-specific optimizations or differences in browser implementation that affect string comparison performance.

In summary, the benchmark tests the performance of simple equality checks versus custom comparison functions for string comparison in JavaScript. The test highlights the importance of choosing an efficient approach to string comparison, especially when working with large strings.

Related benchmarks:

large string comparison1 (version: 0)

Worst case large string comparison.

Comparing performance of: 1MB string comparison vs 2MB string comparison vs 10MB string comparison vs 1MB string comparison+ vs 2MB string comparison+ vs 10MB string comparison+

Created: 2 years ago by: Guest

Jump to the latest result

1MB string comparison

2MB string comparison

10MB string comparison

1MB string comparison+

2MB string comparison+

10MB string comparison+

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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