Benchmark: Delete Pair vs Create New Dict v2

HTML Preparation code:

Object

Script Preparation code:

var obj = {}

for (var i = 0; i <= 1000000; i += 1) {
  obj[i] = i;
}

Tests:

delete
for (var key in obj) { delete obj[key]; }
create/assign dict
obj = {};

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
delete
create/assign dict

Fastest: N/A

Slowest: N/A

Latest run results:

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

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**Benchmark Definition and Preparation Code**

The benchmark definition is a JSON object that describes two test cases: `Delete Pair` and `Create New Dict v2`. The `Script Preparation Code` section sets up an empty object (`obj`) with 1,000,001 properties, where each property has the same key-value pair as its index (e.g., `obj[0] = 0`, `obj[1] = 1`, and so on).

**Options Compared**

The two test cases compare two approaches:

1. **Delete Pair**: This approach iterates over an object's keys using a traditional `for...in` loop, deletes each key-value pair, and repeats this process.
2. **Create New Dict v2**: This approach creates a new empty object (`obj = {}`) and assigns it to the variable `obj`. The idea is that this approach reduces memory allocation overhead compared to deleting an existing object.

**Pros and Cons**

* **Delete Pair**:
	+ Pros: Easy to understand, straightforward implementation.
	+ Cons: Slow due to the need to delete each key-value pair individually.
* **Create New Dict v2**:
	+ Pros: Reduces memory allocation overhead, potentially faster.
	+ Cons: Requires creating a new object, which can be slower than modifying an existing one.

Other considerations:

* The `for...in` loop used in the `Delete Pair` test case is not the most efficient way to iterate over an object's keys. A better approach would use `Object.keys()` or `for...of` loops.
* The `obj = {}` assignment creates a new object, which may lead to unexpected behavior if not properly handled.

**Library and Special JS Features**

There are no explicit libraries used in this benchmark. However, the `Delete Pair` test case relies on the JavaScript engine's built-in behavior for deleting properties from an object.

No special JavaScript features or syntax are explicitly used in either test case.

**Alternatives**

Other approaches to compare in this benchmark could include:

* Using a `Set` data structure to delete key-value pairs (instead of an object).
* Comparing the performance of different garbage collection algorithms.
* Adding more complex properties to the object (e.g., nested objects, arrays) to increase the number of deletions.

Keep in mind that these alternatives would require modifications to the benchmark definition and preparation code.

Related benchmarks:

Delete Pair vs Create New Dict v2 (version: 0)

Comparing performance of: delete vs create/assign dict

Created: 4 years ago by: Guest

Jump to the latest result

delete

create/assign dict

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):