var arr = [1, 4, 2]
arr.unshift(3)
arr.push(3)
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
.unshift() | |
.push() |
Test name | Executions per second |
---|---|
.unshift() | 509123.5 Ops/sec |
.push() | 33170938.0 Ops/sec |
I'd be happy to help you understand the benchmark and its results.
Benchmark Overview
The benchmark is designed to compare the performance of two JavaScript methods: arr.push()
and arr.unshift()
. The test creates an array arr
with initial values [1, 4, 2]
, then pushes or unshifts a value (3
) onto the array. The benchmark measures how many times each operation can be executed per second.
Script Preparation Code
The script preparation code is:
var arr = [1, 4, 2];
This creates an array arr
with initial values [1, 4, 2]
.
Html Preparation Code
There is no html preparation code provided.
Options Compared
Two options are compared in this benchmark:
.push()
: This method appends a value to the end of the array..unshift()
: This method inserts a value at the beginning of the array.Pros and Cons of Each Approach
Here are some pros and cons of each approach:
.push()
:.unshift()
: Library Used
There is no explicit library used in this benchmark. The test relies on the built-in JavaScript methods push()
and unshift()
.
Special JS Features or Syntax
This benchmark does not use any special JavaScript features or syntax.
Other Considerations
.push()
and .unshift()
have similar memory allocation patterns, but .push()
may require more memory allocations for large arrays..push()
and .unshift()
might be affected by cache locality. For example, when using push()
, the CPU can load elements from cache without having to access the array's middle indices.Alternatives
If you want to create a similar benchmark or test other JavaScript methods, consider using a testing framework like Jest or Mocha, which provides more advanced features and flexibility for creating custom benchmarks. Additionally, you may want to explore benchmarking libraries like Benchmark.js or micro-benchmarking frameworks that provide additional features and tools for writing high-quality benchmarks.
For example, here is an alternative benchmark definition using the Benchmark.js library:
const b = require('benchmark');
b.add('push', function() {
var arr = [1, 4, 2];
while (arr.length < 10000) arr.push(3);
});
b.add('unshift', function() {
var arr = [1, 4, 2];
while (arr.length < 10000) arr.unshift(3);
});
This code creates two benchmarks using Benchmark.js: push
and unshift
. The tests use a loop to append or unshift values onto the array until it reaches 10,000 elements.