Benchmark: map vs object - key access (string key2)

Script Preparation code:

var items = Array.from(Array(1000), (_, x) => ({
    key: "abc"+x+"cde",
    value: x * 10
}));

var objContainer = {};
var mapContainer = new Map();

for (let i = 100; i >= 0; i--) {
    const index = Math.floor(Math.random() * 1000);
    const item = items[index];
    objContainer[item.key] = item;
    mapContainer.set(item.key, item)
}

Tests:

Object access
items.forEach(item => objContainer[item.value])
Map get
items.forEach(item => mapContainer.get(item.value))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object access
Map get

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Overview**

The benchmark measures the performance difference between accessing data in an object versus using a Map to store and retrieve data. The test case uses a custom array of objects, where each object has a unique key (generated by concatenating strings) and a value. The benchmark prepares two containers: `objContainer` (an object) and `mapContainer` (a Map), and populates them with the same data.

**Options Compared**

There are two main options being compared:

1. **Object Access**: The first test case uses an object (`objContainer`) to store and retrieve data using the dot notation (`item.value`). This is a simple key lookup operation.
2. **Map Get**: The second test case uses a Map (`mapContainer`) to store and retrieve data using the `get()` method, which takes a string key as an argument.

**Pros and Cons**

* **Object Access**:
	+ Pros: Simple and intuitive, easy to implement, and widely supported.
	+ Cons: May be slower than Map-based lookups due to object lookup overhead (e.g., hash table searching).
* **Map Get**:
	+ Pros: Optimized for key lookups, with an average time complexity of O(1), making it generally faster than object access.
	+ Cons: Requires a Map object to be created and maintained, which may have additional memory and processing overhead.

**Library Usage**

In this benchmark, the `Array.from()` method is used to create an array from an iterable (in this case, another array). This method is a modern JavaScript feature introduced in ECMAScript 2015 (ES6).

**Special JS Feature/Syntax**

None mentioned.

**Other Considerations**

* The use of a random array index (`index = Math.floor(Math.random() * 1000);`) introduces variability in the benchmark results, which may affect the accuracy of the comparison.
* The size of the data set (1,000 objects) is relatively small, and it's unclear how the performance would scale with larger datasets.

**Alternatives**

If you wanted to compare these options using different libraries or approaches, here are some alternatives:

1. **Array-based approach**: Instead of using an object or a Map, you could use an array to store the data and iterate through it to access the values.
2. **IndexedDB**: You could use IndexedDB, a client-side storage system provided by modern browsers, to store and retrieve data in a more efficient manner.
3. **Other libraries**: Depending on your specific requirements, you might consider using other libraries like Lodash or Underscore.js for key lookups and manipulations.

Keep in mind that these alternatives would likely change the nature of the benchmark and may not directly compare to the object access and Map get options.

Related benchmarks:

map vs object - key access (string key2) (version: 0)

Comparing performance of: Object access vs Map get

Created: 3 years ago by: Guest

Jump to the latest result

Object access

Map get

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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