Benchmark: instanceof vs number

Script Preparation code:

var obj = {a:2};

Tests:

instanceof
obj instanceof Object
number
obj.a === 2

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
instanceof
number

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:120.0) Gecko/20100101 Firefox/120.0

Browser/OS: Firefox 120 on Windows

View result in a separate tab

Test name	Executions per second
instanceof	309863648.0 Ops/sec
number	2025309696.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Definition**

The provided JSON represents a benchmark definition, which outlines the test case and its requirements. In this case, there are two test cases:

1. `instanceof vs number`: This test case compares the performance of using `instanceof` versus comparing with a literal value (`===`) to check if an object is equal to a certain property value.
2. The second test case has no description or preparation code, but its benchmark definition is `obj instanceof Object`, which tests whether the `instanceof` operator returns true for the given object.

**Options Compared**

In the first test case, two approaches are compared:

1. `typeof obj === "object"` (not shown in the JSON, but assumed)
2. `obj instanceof Object`

The pros and cons of these approaches are:

* `typeof obj === "object"`:
	+ Pros: This method is concise and easy to read.
	+ Cons: It can return false positives if the object's constructor is not a function (e.g., `new Date()`).
* `obj instanceof Object`:
	+ Pros: This method is more precise, as it only returns true for objects created using the `Object` constructor.
	+ Cons: It may be slower due to the overhead of checking the prototype chain.

**Library Used**

In the second test case, no library is explicitly mentioned. However, since the test involves checking if an object is equal to a certain property value (`obj.a === 2`), it's likely that the `===` operator uses a internal method that checks the values using a library like ECMAScript.

**Special JS Feature or Syntax**

There are no special features or syntax used in these benchmark definitions.

**Other Considerations**

When writing microbenchmarks, consider the following:

1. **Use meaningful names**: Choose descriptive names for your test cases and variables to ensure readability.
2. **Keep it simple**: Avoid using complex logic or optimizations that might skew the results.
3. **Test a variety of scenarios**: Include different edge cases and corner cases to ensure robustness.
4. **Use precise data types**: Use `Number` instead of `Number` (with quotes) for numeric comparisons.

**Alternatives**

Some alternatives to MeasureThat.net include:

1. jsbench.org: A popular online platform for running JavaScript benchmarks.
2. JSHunter: A tool for optimizing JavaScript performance by analyzing execution patterns.
3. Benchmarking libraries like benchmarkjs or micro-benchmark, which provide a standardized way of writing and executing benchmarks.

Keep in mind that the choice of benchmarking platform or library depends on your specific use case, requirements, and personal preferences.

Related benchmarks:

instanceof vs number (version: 0)

Comparing performance of: instanceof vs number

Created: 2 years ago by: Guest

Jump to the latest result

instanceof

number

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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