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push vs index123
(version: 0)
Comparing performance of:
Array.push vs Array[index]
Created:
3 years ago
by:
Guest
Go to the latest result
Tests:
Array.push
const elements = document.all; const amount = elements.length; const arr = []; for (let i = 0; i < amount; i += 1) arr.push(elements[i]);
Array[index]
const elements = document.all; const amount = elements.length; const arr = []; for (let i = 0; i < amount; i += 1) arr[i] = elements[i];
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
Array.push
Array[index]
Fastest:
N/A
Slowest:
N/A
Latest run results:
Run details:
(Test run date:
8 months ago
)
User agent:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36
Browser/OS:
Chrome 143 on Mac OS X 10.15.7
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Embed Benchmark Result
<iframe src="https://measurethat.net/Embed?id=622030" width="100%" height="500px"></iframe>
Array.push
2.2M/s
Array[index]
2.1M/s
View exact numbers
Test name
Executions per second
✓
Array.push
2,152,859 Ops/sec
Array[index]
2,125,299 Ops/sec
Autogenerated LLM Summary
(model
llama3.2:3b
, generated one year ago):
Let's break down the provided benchmarking test cases and explain what's being tested, compared, and considered. **Benchmark Definition** The provided JSON defines two benchmark tests: 1. `push vs index123` 2. `Array.push` (individual test case) 3. `Array[index]` (individual test case) **What is being tested?** In general, the benchmarks are testing how different JavaScript approaches affect the performance of a specific operation: accessing and modifying elements in an array. The two individual test cases: * `Array.push`: Measures the time it takes to push a large number of elements onto an empty array. * `Array[index]`: Measures the time it takes to access elements in an array by their index, without pushing new elements onto the array. **Options compared** In both test cases, two approaches are being compared: 1. **Push-based approach**: The array is initialized with a large number of dummy elements (e.g., `document.all`) and then pushed new elements onto the end of the array using `arr.push(elements[i])`. 2. **Index-based access**: The array is initialized with a large number of dummy elements, but instead of pushing new elements, individual elements are accessed directly by their index: `arr[i] = elements[i]`. **Pros and Cons** **Push-based approach (Array.push)** Pros: * This method can be used when you need to add multiple elements to the end of an array. * It may be more efficient if the array is already large, as it avoids the overhead of accessing individual elements. Cons: * Creating a new element for each push operation can lead to increased memory allocation and garbage collection overhead. * This method can lead to slower performance due to the repeated accesses to `elements[i]`. **Index-based access (Array[index])** Pros: * This method is more efficient when you need to access individual elements by their index, as it avoids the overhead of creating new elements. * It may be faster for large arrays with many fixed-size indices. Cons: * If the array contains a small number of elements or if the index calculation is complex, this approach can lead to slower performance due to the repeated accesses to `elements[i]`. * This method assumes that the array is fixed-size and doesn't account for potential changes or null values. **Other considerations** * The use of `document.all` as a placeholder element may introduce additional overhead due to its dynamic nature. * Modern JavaScript engines (e.g., V8, SpiderMonkey) have optimized garbage collection algorithms to minimize memory allocation and deallocation, reducing the impact of push-based approach on performance. **Library usage** There is no explicit library mentioned in the provided benchmarking test cases. However, the use of `document.all` implies that the code might be targeting older browsers or environments where `document.querySelector` or other DOM query methods are not available. If any special JS features or syntax are used, it's not explicitly mentioned in this case.
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