Benchmark: Test filter and map123

Script Preparation code:

testCase = new Array(100000).fill(1).map(() => Math.random() > 0.5 ? {id: '123'} : undefined)

Tests:

map then filter
testCase.map(t => t ? t.id : undefined).filter(t => !t)
filter tehn map
testCase.filter(t => t).map(t => t.id)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
map then filter
filter tehn map

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and individual test cases to understand what is being tested.

**Benchmark Definition**

The benchmark definition is a JSON object that contains information about the script preparation code, HTML preparation code (which is empty in this case), and a brief description. The script preparation code defines an array `testCase` with 100,000 elements, each filled with either an object `{id: '123'}` or `undefined`. This array will be used to test filtering and mapping operations.

**Individual Test Cases**

There are two individual test cases defined:

1. **"map then filter"**: This test case applies the `filter` method to the `testCase` array, which removes elements that are `undefined`, and then applies the `map` method to the resulting array, which extracts the `id` property from each element.
2. **"filter tehn map"**: This test case applies the `filter` method to the `testCase` array, which removes elements that are not objects (i.e., elements with `undefined` `id`), and then applies the `map` method to the resulting array, which extracts the `id` property from each element.

**Options Compared**

The two test cases compare the performance of applying `filter` followed by `map`, versus applying `map` followed by `filter`. This is a common benchmarking pattern to test the efficiency of JavaScript engines in handling array operations.

**Pros and Cons of Different Approaches**

1. **"map then filter"**: This approach can be beneficial if the filter operation is computationally expensive or if the resulting array needs to be processed further before mapping. However, it may lead to slower performance if the filter operation removes a large number of elements.
2. **"filter tehn map"**: This approach avoids removing unnecessary elements upfront, which can improve performance in cases where the filtered array still needs to be processed. However, it requires an additional iteration over the original array.

**Library Usage**

There is no explicit library usage mentioned in the benchmark definition or individual test cases. The `Array.prototype.filter` and `Array.prototype.map` methods are built-in JavaScript methods that operate on arrays.

**Special JS Features or Syntax**

There are no specific JavaScript features or syntax mentioned in this benchmark definition. However, note that the use of `undefined` as a value in the `testCase` array may indicate a test case for handling null and undefined values in JavaScript operations.

**Other Alternatives**

Other alternatives to benchmarking filtering and mapping operations include:

* **Profiling**: Profiling tools like V8 Inspector (in Chrome) or Node.js Inspector can provide detailed information about the execution time of specific functions or blocks of code.
* **Microbenchmarks with different data structures**: Benchmarking similar operations on different data structures, such as arrays vs. linked lists, or objects vs. arrays, can provide additional insights into the performance characteristics of JavaScript engines.
* **Real-world scenarios**: Benchmarking real-world scenarios that involve filtering and mapping operations, such as processing user input data or image processing pipelines, can help evaluate the performance of JavaScript engines in more complex and realistic contexts.

Keep in mind that benchmarking is an essential part of software development, and these alternatives can provide valuable insights into the performance characteristics of JavaScript engines.

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.101 Safari/537.36

Browser/OS: Chrome 91 on Linux

View result in a separate tab

Test name	Executions per second
map then filter	80.3 Ops/sec
filter tehn map	311.6 Ops/sec

Related benchmarks:

Test filter and map123 (version: 0)

Comparing performance of: map then filter vs filter tehn map

Created: 3 years ago by: Guest

Jump to the latest result

map then filter

filter tehn map

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):