Benchmark: Map vs Object -- 2

Script Preparation code:

var map = new Map();
var obj = {};

var i = 0, count = 1000, a;

Tests:

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

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map lookup
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):

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Let's break down what is being tested in this benchmark.

The test case compares the performance of two data structures: Maps (in JavaScript) and Objects. Specifically, it measures how quickly you can:

1. **Create** 1000 key-value pairs for both data structures.
2. **Look up** the value associated with a given key using the `get()` method for both data structures.

The test uses the same preparation code to create both data structures: `map` and `obj`. The only difference lies in how the values are assigned to the keys:

* In the Map case, each key-value pair is explicitly created using the `set()` method.
* In the Object case, each property is added directly to the object using dot notation (`obj[i] = i;`).

Now, let's consider the pros and cons of these approaches:

**Map approach:**

Pros:

* More explicit control over data structure creation
* Easier to manage keys and values independently

Cons:

* May incur additional overhead due to the `set()` method call
* Less intuitive for developers familiar with Object notation

**Object notation (dot notation):**

Pros:

* More intuitive for developers familiar with Object notation
* Can be more concise and easier to read

Cons:

* Less explicit control over data structure creation
* May lead to accidental key-value pair assignments

Let's take a look at the test results. Both tests were run on the same browser, Chrome 84, on a Linux desktop.

The results show that, for this specific benchmark, **Object notation (dot notation)** performs slightly better than Map lookup with explicit key-value pairs. However, it's essential to note that these results are specific to this particular test case and may not generalize across all scenarios.

Other alternatives:

* Instead of using dot notation, you could also use bracket notation (`obj[i] = i;`) or the `in` operator (`i in obj && obj[i] === i;`).
* You could also explore other data structures like Arrays or Sets, which might have different performance characteristics.
* For larger datasets, caching and optimizing memory allocation might be crucial to achieve optimal performance.

Keep in mind that these are just some general considerations, and the actual performance impact of these alternatives will depend on various factors, including system resources, compiler optimizations, and other external influences.

Related benchmarks:

Map vs Object -- 2 (version: 0)

Lookup of map vs object

Comparing performance of: Map lookup vs Obj lookup

Created: 5 years ago by: Guest

Jump to the latest result

Map lookup

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):