Benchmark: sdfsf22drl Delete vs set undefined

Script Preparation code:

var obj = {};
for (let i = 0; i < 999; i++) {
  obj[`a_${i}`] = i;
}

Tests:

Delete
for (let i = 0; i < 999; i++) { delete obj[`a_${i}`]; }
Set undefined
for (let i = 0; i < 999; i++) { obj[`a_${i}`] = undefined; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Delete
Set undefined

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 11_1_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36

Browser/OS: Chrome 87 on Mac OS X 11.1.0

View result in a separate tab

Test name	Executions per second
Delete	4875.5 Ops/sec
Set undefined	3109.3 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its results.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark that compares two approaches: deleting properties from an object versus setting them to `undefined`.

Here's what's being tested:

* The script preparation code creates an empty object (`var obj = {};`) and then populates it with 999 properties using a `for` loop. Each property is named in the format `a_<i>`, where `<i>` is the iteration number.
* The first test case, "Delete", uses a `delete` statement to remove each of these properties from the object. This approach is being compared against...
* ...the second test case, "Set undefined", which sets each property to `undefined` using the assignment operator (`=`). This approach is also being tested.

**Options Compared**

The two options being compared are:

1. **Deleting**: Using the `delete` keyword to remove properties from an object.
2. **Setting to undefined**: Setting properties to `undefined` using the assignment operator (`=`).

**Pros and Cons of Each Approach**

**Deleting:**

Pros:

* Can be faster, as it involves a single operation to remove a property.
* May be more efficient in certain situations, such as when dealing with large objects.

Cons:

* Can throw an error if the property does not exist on the object.
* May not work correctly in all browsers or environments.

**Setting to undefined:**

Pros:

* Always sets the property value to `undefined`, regardless of whether it existed before.
* Does not throw errors, even if the property does not exist.

Cons:

* May be slower, as it involves two operations (assigning a new value and then setting it to `undefined`).
* May use more memory, depending on the object's structure.

**Other Considerations**

The benchmark also considers the device platform (Desktop), browser version (Chrome 87), operating system (Mac OS X 11.1.0), and number of executions per second.

**Libraries and Special JS Features**

There are no libraries mentioned in the provided JSON, but the `delete` keyword is a built-in JavaScript feature.

**Test Case Variations**

The test cases use different approaches to modify the object properties. These variations help ensure that the benchmark results accurately reflect the performance characteristics of each approach.

Now, let's look at the latest benchmark results...

According to the provided JSON, the benchmark has been run on two browsers (Chrome 87) and yielded the following results:

| Test Name | Executions Per Second |
| --- | --- |
| Delete | 4875.45068359375 |
| Set undefined | 3109.2705078125 |

These results indicate that deleting properties from an object is significantly faster than setting them to `undefined`, at least in this specific benchmark scenario.

**Other Alternatives**

If you're interested in exploring alternative approaches, here are a few options:

* Using `Object.prototype.hasOwnProperty.call(obj, 'a_<i>')` instead of bracket notation (`obj['a_<i>']`) could provide different results.
* Comparing the performance of other JavaScript engines, such as SpiderMonkey (Firefox) or V8 (Node.js), might yield interesting results.

Keep in mind that benchmarking can be complex and influenced by many factors. Always consider the specific use case and environment when running benchmarks to ensure accurate results.

Related benchmarks:

sdfsf22drl Delete vs set undefined (version: 0)

Comparing performance of: Delete vs Set undefined

Created: 3 years ago by: Guest

Jump to the latest result

Delete

Set undefined

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):