Benchmark: deep json spread vs flat

Script Preparation code:

var deepJson = [
  [{
	"items":
		{
			"item":
				[
					{
						"id": "0001",
						"type": "donut",
						"name": "Cake",
						"ppu": 0.55,
						"batters":
							{
								"batter":
									[
										{ "id": "1001", "type": "Regular" },
										{ "id": "1002", "type": "Chocolate" },
										{ "id": "1003", "type": "Blueberry" },
										{ "id": "1004", "type": "Devil's Food" }
									]
							},
						"topping":
							[
								{ "id": "5001", "type": "None" },
								{ "id": "5002", "type": "Glazed" },
								{ "id": "5005", "type": "Sugar" },
								{ "id": "5007", "type": "Powdered Sugar" },
								{ "id": "5006", "type": "Chocolate with Sprinkles" },
								{ "id": "5003", "type": "Chocolate" },
								{ "id": "5004", "type": "Maple" }
							]
					},

				]
		}
}],
  [{
	"items":
		{
			"item":
				[
					{
						"id": "0001",
						"type": "donut",
						"name": "Cake",
						"ppu": 0.55,
						"batters":
							{
								"batter":
									[
										{ "id": "1001", "type": "Regular" },
										{ "id": "1002", "type": "Chocolate" },
										{ "id": "1003", "type": "Blueberry" },
										{ "id": "1004", "type": "Devil's Food" }
									]
							},
						"topping":
							[
								{ "id": "5001", "type": "None" },
								{ "id": "5002", "type": "Glazed" },
								{ "id": "5005", "type": "Sugar" },
								{ "id": "5007", "type": "Powdered Sugar" },
								{ "id": "5006", "type": "Chocolate with Sprinkles" },
								{ "id": "5003", "type": "Chocolate" },
								{ "id": "5004", "type": "Maple" }
							]
					},

				]
		}
}]
]

Tests:

spread
const a = [...deepJson, ...deepJson, ...deepJson]
flat
const a = [deepJson, deepJson, deepJson].flat()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
spread
flat

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
spread	7909334.5 Ops/sec
flat	4332786.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring the performance of JavaScript code is crucial in understanding how different approaches can affect execution time.

In this benchmark, we have two test cases: `spread` and `flat`. Both tests involve working with nested JSON data.

**Benchmark Definition**

The benchmark definition for each test case is provided as a string. For the `spread` test, it's:

```javascript
const a = [...deepJson, ...deepJson, ...deepJson];
```

And for the `flat` test, it's:

```javascript
const a = [deepJson, deepJson, deepJson].flat();
```

**Options Compared**

In this benchmark, we have two options being compared: using the spread operator (`...`) and using the `flat()` method.

The spread operator is used to create a new array by copying elements from an existing array. In this case, it's used to duplicate the `deepJson` array three times.

On the other hand, the `flat()` method is used to flatten an array of arrays into a single-level array. Here, it's used to concatenate three instances of the `deepJson` array.

**Pros and Cons**

**Spread Operator (`...`)**

Pros:

* More intuitive and readable way to duplicate an array
* Works with any type of iterable (not just arrays)

Cons:

* Can be less efficient than using `flat()` for large datasets, as it creates a new array for each element
* Does not preserve the original order of elements

**Flat() Method**

Pros:

* More efficient than spread operator for large datasets, as it only creates one new array
* Preserves the original order of elements

Cons:

* Less intuitive and readable way to duplicate an array
* Works with arrays only

**Other Considerations**

When working with nested JSON data, the performance difference between using the spread operator and `flat()` method may be negligible unless dealing with extremely large datasets. However, if you need to optimize performance for very large JSON data, using `flat()` might be a better choice.

In terms of readability and maintainability, the spread operator is generally considered more intuitive and easier to read than `flat()`. This makes it easier to understand the intent of the code and follow its logic.

**Latest Benchmark Results**

According to the latest benchmark results, Chrome 123 performs slightly better on the `spread` test (with an execution rate of 7909334.5 executions per second) compared to the `flat` test (with an execution rate of 4332786.0 executions per second). However, it's essential to note that these results may vary depending on the specific environment and hardware used.

Overall, this benchmark highlights the importance of understanding how different approaches can affect performance in JavaScript code, particularly when working with nested data structures.

Related benchmarks:

deep json spread vs flat (version: 0)

Comparing performance of: spread vs flat

Created: 2 years ago by: Guest

Jump to the latest result

spread

flat

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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