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Abe's weird loop thing
(version: 0)
A loop with an illegal array access seems more efficient than one without… what's up?
Comparing performance of:
With array access vs Without array access
Created:
4 years ago
by:
Guest
Jump to the latest result
Tests:
With array access
let data = ''; for (var i = 0; i < 1000; i++) { data += `${Math.random()}\n`; } const cache = {}; for (let x = 0; x <= 100e3; x++) { const split = data.split("\n"); cache[data]; }
Without array access
let data = ''; for (var i = 0; i < 1000; i++) { data += `${Math.random()}\n`; } for (let x = 0; x <= 100e3; x++) { const split = data.split("\n"); }
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
With array access
Without array access
Fastest:
N/A
Slowest:
N/A
Latest run results:
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Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's dive into the world of JavaScript microbenchmarks! **What is being tested?** The provided JSON represents two individual test cases for a JavaScript benchmark. Each test case measures the performance of a specific piece of code. In the first test case, "With array access," the code attempts to access an element outside the bounds of an array using invalid indexing (`x <= 100e3`). In contrast, the second test case, "Without array access," doesn't attempt any illegal array access. Instead, it simply splits a large string into an array using `data.split("\n");`. **Options compared:** The two options being compared are: 1. **With array access**: This option attempts to access an element outside the bounds of an array using invalid indexing. 2. **Without array access**: This option does not attempt any illegal array access. **Pros and Cons:** * **With array access**: + Pros: May be more efficient due to less overhead in handling invalid array indices. + Cons: Invalid array indexing can lead to unexpected behavior, crashes, or security vulnerabilities. * **Without array access**: + Pros: Safer and more predictable, with fewer opportunities for errors. + Cons: Might incur additional overhead due to the extra work required to handle valid indexing. Other considerations: * In a real-world scenario, it's generally recommended to prioritize code safety and avoid accessing elements outside the bounds of an array. The "Without array access" option might be more desirable in terms of security and reliability. * However, if performance is critical and you're working on a specific use case where array indexing is unavoidable, the "With array access" option might be acceptable. **Library:** There doesn't seem to be any explicit library mentioned in the provided JSON. However, it's likely that the benchmark utilizes libraries like UAS (User Agent String) or JavaScript core implementations from browsers like Chrome or Firefox. **Special JS feature or syntax:** The test case uses invalid array indexing (`x <= 100e3`) and string concatenation (`data += `${Math.random()}\\n`;\r\n`). This is a valid JavaScript syntax, but it's not recommended for production code due to its potential security vulnerabilities. Other alternatives: * If you want to compare the performance of different array access methods (e.g., using `array[index]`, `array.length > index && array[index]`, or `array.slice(0, index)`), you could add additional test cases to the benchmark. * You might also consider testing the performance of other string manipulation operations, such as regular expression matching or substring extraction. Keep in mind that the primary goal of a benchmark is to measure the performance of specific code snippets. The provided JSON seems to be focused on comparing the performance of two distinct options: "With array access" and "Without array access."
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