Benchmark: Map vs Object assign

Script Preparation code:

var map = new Map();
var obj = {};

var i = 0, count = 5000, a;

Tests:

Map assign
for (i = 0; i < count; i++) { map.set(i, 'test'); }
Obj lookup
for (i = 0; i < count; i++) { obj[i] = 'test'; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map assign
Obj lookup

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases.

**Benchmark Definition**

The benchmark is designed to compare the performance of two data structures in JavaScript: Maps (also known as Hash Tables or associative arrays) and objects (specifically, property assignment). The goal is to measure how quickly these two data structures can be populated with a large number of key-value pairs.

**Options Compared**

There are two options being compared:

1. **Map assign**: This option uses the `set()` method of the Map object to add new key-value pairs.
2. **Obj lookup**: This option uses property assignment (e.g., `obj[i] = 'test'`) to add new key-value pairs.

**Pros and Cons**

* **Map assign**:
	+ Pros: Maps are designed for fast lookups, so using the `set()` method is likely to be efficient.
	+ Cons: The `set()` method may incur additional overhead due to its internal implementation (e.g., hash table resizing).
* **Obj lookup**:
	+ Pros: Property assignment is a simple and lightweight way to add new key-value pairs.
	+ Cons: This approach can lead to slower performance due to the need for sequential lookups.

**Library and Purpose**

In this benchmark, no libraries are explicitly mentioned. However, it's worth noting that many JavaScript engines and browsers have built-in optimizations and implementations for Maps and objects.

**Special JS Feature or Syntax**

This benchmark does not use any special JavaScript features or syntax, such as async/await, generators, or Promises. It's designed to be straightforward and easy to understand.

**Other Considerations**

When designing benchmarks like this one, it's essential to consider factors that may affect performance, such as:

* Cache behavior: How do the different approaches interact with caches?
* Garbage collection: How does the JavaScript engine manage memory allocation and deallocation for these data structures?
* Browser-specific optimizations: Some browsers have optimized implementations of Maps and objects that might not be present in other engines.

**Alternative Benchmarks**

Other alternatives to this benchmark could include:

1. **Sorting vs Array methods**: Compare the performance of different sorting algorithms (e.g., QuickSort, Merge Sort) against built-in array methods like `sort()`.
2. **Regexp vs String methods**: Measure the performance of regular expressions versus built-in string methods for tasks like splitting strings or replacing substrings.
3. **Web Worker vs Main thread**: Compare the performance of web workers (background threads) with the main thread in JavaScript applications.

Keep in mind that these alternatives will likely have different results and requirements, depending on the specific use case and hardware being tested.

Related benchmarks:

Map vs Object assign (version: 0)

Lookup of map vs object

Comparing performance of: Map assign vs Obj lookup

Created: 5 years ago by: Guest

Jump to the latest result

Map assign

Obj lookup

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):