Benchmark: incrementing 1000

Tests:

--i
for (let i = 1000; --i;) { console.log(i); }
i--
for (let i = 1000; i--;) { console.log(i); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
--i
i--

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
--i	547.1 Ops/sec
i--	547.6 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 what's being tested in this benchmark.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark called "incrementing 1000". The benchmark definition is simple: it consists of a single `for` loop that increments a variable `i` from 1000 down to 1, logging each value to the console. There are two variations:

* One variation uses a decrement operator (`--i`) before the condition in the `while` loop (e.g., `for (let i = 1000; --i;)`). We'll call this variant "-i".
* The other variation uses a post-decrement operator (`i--`) after the condition in the `while` loop (e.g., `for (let i = 1000; i--;)`). We'll call this variant "i--".

**Options Compared**

The benchmark compares two approaches:

1. `-i`: uses a decrement operator before the condition.
2. `i--`: uses a post-decrement operator after the condition.

These options are compared in terms of performance, which is measured by the number of executions per second (ExecutionsPerSecond).

**Pros and Cons**

* `-i`:
	+ Pros: potentially more efficient due to the possibility of early loop exit.
	+ Cons: might cause issues with certain edge cases or loop invariant properties.
* `i--`:
	+ Pros: often preferred in C-like languages where post-decrement is more idiomatic.
	+ Cons: might be slower due to the extra operation.

**Library and Special JS Features**

There are no libraries used in this benchmark, and there are no special JavaScript features (like async/await or generators) being tested. The focus is solely on comparing the performance of two simple `for` loop variations.

**Other Considerations**

When choosing between `-i` and `i--`, consider the following:

* If you're working with a language that has strict control over loop behavior (e.g., Rust), the difference might be negligible.
* If you're optimizing for memory usage or reducing stack size, `-i` might be a better choice due to its potential for early loop exit.
* In general, unless performance is critical, the choice between these two variants should not have a significant impact on code readability or maintainability.

**Alternative Approaches**

Other alternatives for this benchmark could include:

1. **using `while` loops**: Instead of `for` loops, you could use `while` loops with manual increment and decrement operations.
2. **using array iteration**: You could iterate over an array using the `forEach` method or a traditional `for` loop with array indices.
3. **using Web Workers**: If performance is critical, you could parallelize the execution of multiple iterations using Web Workers.

However, these alternatives would likely change the nature of the benchmark significantly and might not be relevant to this specific use case.

Related benchmarks:

incrementing 1000 (version: 1)

--i vs i--

Comparing performance of: --i vs i--

Created: 3 years ago by: Registered User

Jump to the latest result

--i

i--

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):