Benchmark: switch vs if - MeasureThat.net

HTML Preparation code:

<div class="test"></div>

Script Preparation code:

var v = 8;

Tests:

switch
switch (true) { case v === 1: break; case v === 2: break; case v === 3: break; case v === 4: break; case v === 5: break; case v === 6: break; case v === 7: break; default: ; }
if
if (v === 1) { } else if (v === 2) { } else if (v === 3) { } else if (v === 4) { } else if (v === 5) { } else if (v === 6) { } else if (v === 7) { } else if (v === 8) { } else { }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
switch
if

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 8 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:143.0) Gecko/20100101 Firefox/143.0

Browser/OS: Firefox 143 on Windows

View result in a separate tab

Test name	Executions per second
switch	42150480.0 Ops/sec
if	37148368.0 Ops/sec

Autogenerated LLM Summary (model llama3.1:latest, generated one year ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition:**

The benchmark is called "switch vs if" and compares the performance of two different programming constructs in JavaScript: `switch` statements and `if-else` chains. The test case uses a variable `v` with a value of 8, which will be used to evaluate both constructs.

**Individual Test Cases:**

There are two test cases:

1. **Switch**: This test case uses a `switch` statement with multiple `case` clauses and a default clause.
2. **If**: This test case uses an `if-else` chain with multiple `else if` conditions, ending with a final `else` clause.

**Latest Benchmark Result:**

The latest benchmark results show the execution performance (ExecutionsPerSecond) of both test cases on a Chrome 65 browser running on Linux. The results are:

* Switch: 1071013.125 executions per second
* If: 983776.125 executions per second

**What's Being Tested?**

In this benchmark, we're testing the performance difference between two JavaScript constructs for conditional execution:

1. **Switch statement**: A `switch` statement allows you to execute different blocks of code based on the value of a variable. It's particularly useful when you have multiple conditions to check.
2. **If-else chain**: An `if-else` chain is used to execute different blocks of code based on the value of a variable, with each condition checked in sequence.

**Library Used:**

None, this benchmark uses pure JavaScript constructs.

**JavaScript Features or Syntax Used:**

* None specific syntax or features are used. The test cases rely only on basic JavaScript constructs (switch statement and if-else chain).

**Pros/Cons of Different Approaches:**

In general:

* **Switch statement**: Pros:
	+ More concise code when dealing with multiple conditions.
	+ Easier to read and maintain for large numbers of conditions.
* Cons:
	+ May be slower than if-else chains due to the overhead of creating a jump table (in older JavaScript engines).
* **If-else chain**: Pros:
	+ Generally faster than switch statements due to the simplicity of the code.
	+ Can be used in situations where the number of conditions is small or dynamic.

**Other Considerations:**

When choosing between `switch` and `if-else` chains, consider the following:

* **Code readability**: If you have a large number of conditions, a switch statement might be more readable due to its concise syntax.
* **Performance**: In general, if-else chains tend to perform better than switch statements. However, modern JavaScript engines (e.g., V8) often optimize `switch` statements, making them comparable in performance.

**Other Alternatives:**

In some cases, you might use a different construct or approach:

* **Object literal with conditions**: You can create an object with properties that correspond to specific conditions and use the `in` operator to check for presence.
* **Function composition**: In modern JavaScript, you can use function composition to chain multiple functions together, creating a more functional programming style.

In this specific benchmark, neither of these alternatives was used.

Related benchmarks:

switch vs if (version: 0)

Comparing performance of: switch vs if

Created: 7 years ago by: Guest

Jump to the latest result

switch

if

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.1:latest, generated one year ago):