Benchmark: Object key access vs array find vs Set

Script Preparation code:

var items = Array.from(Array(1000), (_,x) => ({key: x, value: x*10}));

var objContainer = {};
var arrContainer = [];
var setContainer = new Set();

for (let i = 100; i >= 0; i--) {
  const index = Math.floor(Math.random() * 1000);
  const item = items[index];
  objContainer[item.key] = item;
  arrContainer.push(item)
  setContainer.add(item)
}

Tests:

Object access
items.forEach(item => objContainer[item.value])
Array find
items.forEach(item => arrContainer.find(containerItem => containerItem.value === item.value))
Set find
items.forEach(item => setContainer.has(item.value))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object access
Array find
Set find

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Object access	40628.7 Ops/sec
Array find	5150.5 Ops/sec
Set find	40421.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the benchmark.

The provided JSON represents a JavaScript microbenchmark test case that measures the performance of three different approaches: object access by key, array find to find an object, and set find to check if an element exists in a set.

**Options being compared:**

1. **Object access by key**: This approach uses the bracket notation (`objContainer[item.key]`) to directly access the value associated with a given key.
2. **Array find**: This approach uses the `find` method to search for an object within the array that matches a certain condition (in this case, `containerItem.value === item.value`).
3. **Set find**: This approach uses the `has` method to check if an element exists in the set.

**Pros and cons of each approach:**

* **Object access by key**: This approach is likely to be the fastest since it directly accesses the value associated with a given key, without the need for searching or iteration. However, this approach may require more memory allocation and deallocation than the other two options.
* **Array find**: This approach can be slower since it requires iterating through the array to find the matching object. Additionally, if the array is not sorted or has a complex structure, the search might take longer. On the other hand, `find` method returns the first match it finds, which can be beneficial in certain scenarios.
* **Set find**: This approach is likely to be faster than array find since sets are typically implemented as hash tables, allowing for constant-time lookups. However, set operations may require additional memory allocation and deallocation.

**Library usage:**

The benchmark uses the following libraries:

* `Array.from`: A method that creates a new Array instance from an iterable or array-like object.
* `Set`: A built-in JavaScript data structure that stores unique values.
* `find` method: A method of arrays that returns the first element that satisfies the provided condition.

**Special JS feature/syntax:**

None mentioned in this benchmark. However, it's worth noting that some modern browsers and Node.js versions may have additional features or optimizations that could affect performance, such as:

* `let const` declarations
* Arrow functions
* Rest parameters
* Spread syntax

These features can be used to optimize the code, but they are not explicitly mentioned in this benchmark.

**Alternatives:**

Other alternatives for accessing elements by key, searching arrays, or checking if an element exists in a set include:

* Using `Object.keys()` and indexing into the resulting array
* Using `indexOf()` method on arrays
* Using `hasOwnProperty()` method on objects

Keep in mind that these alternatives may have different performance characteristics compared to the approaches tested in this benchmark.

Related benchmarks:

Object key access vs array find vs Set (version: 0)

Test speed of object access by key vs array find to find object

Comparing performance of: Object access vs Array find vs Set find

Created: one year ago by: Guest

Jump to the latest result

Object access

Array find

Set find

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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