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

Autogenerated LLM Summary (model llama3.2:3b, generated one month 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.

Latest run results:

Run details: (Test run date: one year 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

Related benchmarks:

instanceof vs number (version: 0)

Comparing performance of: instanceof vs number

Created: one year ago by: Guest

Jump to the latest result

instanceof

number

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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