Benchmark: Array/Set/Map/Object Iteration

Script Preparation code:

var obj = {"one": true, "two": true, "three": true, "four": true, "five": true, "six": true, "seven": true, "eight": true, "nine": true, "ten": true};
var map = new Map([["one", true], ["two", true], ["three", true], ["four", true], ["five", true], ["six", true], ["seven", true], ["eight", true], ["nine", true], ["ten", true]]);

var arr = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten"];
var set = new Set(["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten"]);

Tests:

Object Iteration
for (const key in obj) { void(obj[key]); }
Array Iteration
for (const element of arr) { void(element); }
Map Iteration
for (const element of map) { void(element); }
Map Iteration (keys)
for (const element of map.keys()) { void(element); }
Map Iteration (values)
for (const element of map.values()) { void(element); }
Set Iteration
for (const element of set) { void(element); }

Historical Performance Data aggregated from 41 community runs

Desktop Results:

Chrome 31 runs

Array Iteration

30.3M/s

Set Iteration

21.1M/s

Map Iteration (values)

20.9M/s

Map Iteration (keys)

18.5M/s

Map Iteration

17.0M/s

Object Iteration

7.1M/s

Fastest: Array Iteration (4.2x faster)

View exact numbers

✓ Array Iteration: 30,315,736 ops/sec
• Set Iteration: 21,063,820 ops/sec
• Map Iteration (values): 20,941,062 ops/sec
• Map Iteration (keys): 18,503,214 ops/sec
• Map Iteration: 17,039,930 ops/sec
• Object Iteration: 7,143,852 ops/sec

Firefox 10 runs

Array Iteration

11.9M/s

Object Iteration

10.8M/s

Set Iteration

3.9M/s

Map Iteration (keys)

3.7M/s

Map Iteration (values)

3.4M/s

Map Iteration

2.6M/s

Fastest: Array Iteration (4.6x faster)

View exact numbers

✓ Array Iteration: 11,921,090 ops/sec
• Object Iteration: 10,800,400 ops/sec
• Set Iteration: 3,874,016 ops/sec
• Map Iteration (keys): 3,717,950 ops/sec
• Map Iteration (values): 3,388,266 ops/sec
• Map Iteration: 2,606,101 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object Iteration
Array Iteration
Map Iteration
Map Iteration (keys)
Map Iteration (values)
Set Iteration

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:144.0) Gecko/20100101 Firefox/144.0

Browser/OS: Firefox 144 on Windows

View result in a separate tab

Array Iteration

5.1M/s

Object Iteration

2.2M/s

Set Iteration

1.4M/s

Map Iteration (values)

1.3M/s

Map Iteration (keys)

1.2M/s

Map Iteration

1.1M/s

View exact numbers

Test name	Executions per second
✓ Array Iteration	5,114,070 Ops/sec
Object Iteration	2,177,168 Ops/sec
Set Iteration	1,364,761 Ops/sec
Map Iteration (values)	1,257,336 Ops/sec
Map Iteration (keys)	1,249,064 Ops/sec
Map Iteration	1,063,932 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the provided benchmark definition and individual test cases.

**Benchmark Definition:**

The benchmark measures the performance of different iteration methods on various data structures: arrays, maps, sets, and objects.

**Data Structures Used:**

1. **Array:** A one-dimensional collection of values, ordered and indexed.
2. **Map:** An unordered collection of key-value pairs.
3. **Set:** An unordered collection of unique values, often used for fast membership testing.
4. **Object:** An unordered collection of key-value pairs, similar to a map.

**Iteration Methods:**

1. **For...in loop:** Iterates over the properties (keys) of an object or array.
2. **For...of loop:** Iterates over the elements of an array.
3. **Map iteration (keys):** Iterates over the keys of a map.
4. **Map iteration (values):** Iterates over the values of a map.
5. **Set iteration:** Iterates over the elements of a set.

**Library Used:**

None, as all data structures are native JavaScript implementations.

**Special Features/Syntax:**

None mentioned in the provided benchmark definition.

**Options Compared:**

The benchmark compares the performance of different iteration methods on each data structure:

* For...in loop vs. For...of loop
* Map iteration (keys) vs. Map iteration (values)
* Array iteration vs. Set iteration

**Pros and Cons:**

1. **For...in loop**:
	* Pros: Often used for objects, easy to implement.
	* Cons: Can iterate over inherited properties, slower than For...of loop.
2. **For...of loop**:
	* Pros: Faster, more efficient for arrays and sets.
	* Cons: Only available in modern JavaScript versions (ECMAScript 2015+).
3. **Map iteration (keys)**:
	* Pros: Provides access to both keys and values without having to iterate over an array or object.
	* Cons: Slower than Map iteration (values) for some use cases.
4. **Map iteration (values)**:
	* Pros: Faster than Map iteration (keys), provides direct access to values.
	* Cons: Does not provide access to keys, requires iterating over an array or object.
5. **Set iteration**:
	* Pros: Fast and efficient for sets.
	* Cons: Not as flexible as other iteration methods.

**Other Considerations:**

* Modern JavaScript versions (ECMAScript 2015+) provide more efficient iteration methods, like For...of loop and Map iteration (values).
* The choice of iteration method depends on the specific use case and performance requirements.
* When working with objects or arrays, consider using the most suitable iteration method based on your needs.

**Alternatives:**

If you're looking for alternatives to this benchmark, you can explore other JavaScript microbenchmarks that test different aspects of performance, such as:

1. **JSPerf**: A popular online tool for comparing the performance of different JavaScript implementations.
2. **Benchmark.js**: A library for writing and running JavaScript benchmarks.
3. **Google Benchmark**: A high-performance benchmarking framework for C++ and JavaScript.

Keep in mind that these alternatives might not provide an identical experience to MeasureThat.net, but they can help you explore different aspects of performance and optimization in your own codebase.

Array/Set/Map/Object Iteration (version: 0)

Comparing performance of: `Object Iteration vs Array Iteration vs Map Iteration vs Map Iteration (keys) vs Map Iteration (values) vs Set Iteration`

Created: 4 years ago by: Guest

Go to the latest result

Object Iteration

Array Iteration

Map Iteration

Map Iteration (keys)

Map Iteration (values)

Set Iteration

Historical Performance Data aggregated from 41 community runs

Desktop Results:

Chrome 31 runs

Firefox 10 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Array/Set/Map/Object Iteration (version: 0)

Comparing performance of: Object Iteration vs Array Iteration vs Map Iteration vs Map Iteration (keys) vs Map Iteration (values) vs Set Iteration

Created: 4 years ago by: Guest

Go to the latest result

Object Iteration

Array Iteration

Map Iteration

Map Iteration (keys)

Map Iteration (values)

Set Iteration

Historical Performance Data aggregated from 41 community runs

Desktop Results:

Chrome 31 runs

Firefox 10 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `Object Iteration vs Array Iteration vs Map Iteration vs Map Iteration (keys) vs Map Iteration (values) vs Set Iteration`