Benchmark: Iterate-Set - MeasureThat.net

Script Preparation code:

var fewItemSet = new Set([1, 2, 3]);
var manyItemSet = new Set(Array.from({ length: 1000 }, (_, i) => i));

Tests:

for of: few items
let result = 0; for (const item of fewItemSet) { result += item; }
for of: many items
let result = 0; for (const item of manyItemSet) { result += item; }
convert to array: few items
let result = 0; const arr = Array.from(fewItemSet); for (let i = arr.length; i--;) { result += arr[i]; }
convert to array: many items
let result = 0; const arr = Array.from(manyItemSet); for (let i = arr.length; i--;) { result += arr[i]; }
native iterator: few items
let result = 0; let val = null; const iter = fewItemSet.values(); while (!(val = iter.next()).done) { result += val.value; }
native iterator: many items
let result = 0; let val = null; const iter = manyItemSet.values(); while (!(val = iter.next()).done) { result += val.value; }
native iterator w/ size: few items
let result = 0; let iter = fewItemSet.values(); for (let i = fewItemSet.size; i--;) { result += iter.next().value; }
native iterator w/ size: many items:
let result = 0; let iter = manyItemSet.values(); for (let i = manyItemSet.size; i--;) { result += iter.next().value; }

Historical Performance Data aggregated from 42 community runs

Desktop Results:

Chrome 34 runs

native iterator: few items

23.9M/s

for of: few items

23.8M/s

native iterator w/ size: few items

13.5M/s

convert to array: few items

8.8M/s

for of: many items

469K/s

native iterator: many items

460K/s

native iterator w/ size: many items:

417K/s

convert to array: many items

389K/s

Fastest: native iterator: few items (61.4x faster)

View exact numbers

✓ native iterator: few items: 23,890,364 ops/sec
• for of: few items: 23,782,940 ops/sec
• native iterator w/ size: few items: 13,513,572 ops/sec
• convert to array: few items: 8,762,310 ops/sec
• for of: many items: 469,226 ops/sec
• native iterator: many items: 460,344 ops/sec
• native iterator w/ size: many items:: 417,295 ops/sec
• convert to array: many items: 388,922 ops/sec

Firefox 8 runs

native iterator w/ size: few items

12.7M/s

for of: few items

11.8M/s

native iterator: few items

11.8M/s

convert to array: few items

10.2M/s

convert to array: many items

96K/s

for of: many items

93K/s

native iterator w/ size: many items:

87K/s

native iterator: many items

85K/s

Fastest: native iterator w/ size: few items (149.7x faster)

View exact numbers

✓ native iterator w/ size: few items: 12,715,137 ops/sec
• for of: few items: 11,798,374 ops/sec
• native iterator: few items: 11,787,056 ops/sec
• convert to array: few items: 10,248,840 ops/sec
• convert to array: many items: 96,008 ops/sec
• for of: many items: 92,899 ops/sec
• native iterator w/ size: many items:: 86,693 ops/sec
• native iterator: many items: 84,926 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for of: few items
for of: many items
convert to array: few items
convert to array: many items
native iterator: few items
native iterator: many items
native iterator w/ size: few items
native iterator w/ size: many items:

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; rv:143.0) Gecko/20100101 Firefox/143.0

Browser/OS: Firefox 143 on Mac OS X 10.15

View result in a separate tab

native iterator w/ size: few items

10.2M/s

for of: few items

9.1M/s

native iterator: few items

9.0M/s

convert to array: few items

6.9M/s

for of: many items

71K/s

native iterator w/ size: many items:

69K/s

native iterator: many items

66K/s

convert to array: many items

52K/s

View exact numbers

Test name	Executions per second
✓ native iterator w/ size: few items	10,198,365 Ops/sec
for of: few items	9,061,966 Ops/sec
native iterator: few items	9,009,638 Ops/sec
convert to array: few items	6,913,932 Ops/sec
for of: many items	71,398 Ops/sec
native iterator w/ size: many items:	68,803 Ops/sec
native iterator: many items	65,620 Ops/sec
convert to array: many items	52,039 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 for a JavaScript microbenchmark. The `Script Preparation Code` section defines two sets, `fewItemSet` and `manyItemSet`, which are used to test different scenarios.

Here's a brief explanation of what's being tested:

*   `Iterate-Set`: This benchmark tests the performance of iterating over a set using three different approaches:
    *   `for...of` loop
    *   Converting the set to an array and iterating over it with a traditional `for` loop
    *   Using a native iterator (`values()`) to iterate over the set

**Options Compared**

The benchmark compares the performance of these three approaches:

*   **For-each loop**: This is a modern JavaScript syntax that allows you to iterate over an iterable (like a set) without creating an intermediate array. It's generally faster and more memory-efficient than traditional `for` loops.
*   **Converting to Array**: In this approach, the set is converted to an array, which requires additional memory allocation. This method can be slower due to the extra overhead of creating an array.

**Pros and Cons**

Here are some pros and cons for each approach:

*   **For-each loop**:
    *   Pros: Faster execution time, less memory usage, more concise code.
    *   Cons: May not work as expected with certain data structures or older JavaScript versions.
*   **Converting to Array**:
    *   Pros: Can be used in older JavaScript versions or with specific data structures that don't support `for...of`.
    *   Cons: Requires additional memory allocation, potentially slower execution time.

**Native Iterator**

The native iterator (`values()`) approach uses a built-in method provided by modern browsers to iterate over sets. This method is generally faster and more efficient than the other two approaches.

*   Pros:
    *   Fastest execution time
    *   Minimal memory usage
    *   Concise code
*   Cons: May not work in older JavaScript versions or with specific data structures.

**Convert to Array**

Converting a set to an array and iterating over it is a common approach, but it may incur additional overhead due to the extra memory allocation required for the array.

**For-each Loop vs. Native Iterator**

In this benchmark, the `for...of` loop and native iterator (`values()`) approaches are generally faster than the converting-to-array approach. This suggests that modern browsers optimize these methods for better performance.

**Conclusion**

The JavaScript microbenchmark demonstrates the importance of choosing the right iteration method depending on the specific use case, data structure, and browser version. While `for...of` loops offer a concise and efficient way to iterate over sets, native iterators can provide even faster execution times in modern browsers.

Iterate-Set (version: 3)

Iterate over a set.

Comparing performance of: `for of: few items vs for of: many items vs convert to array: few items vs convert to array: many items vs native iterator: few items vs native iterator: many items vs native iterator w/ size: few items vs native iterator w/ size: many items:`

Created: 5 years ago by: Registered User

Go to the latest result

for of: few items

for of: many items

convert to array: few items

convert to array: many items

native iterator: few items

native iterator: many items

native iterator w/ size: few items

native iterator w/ size: many items:

Historical Performance Data aggregated from 42 community runs

Desktop Results:

Chrome 34 runs

Firefox 8 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Iterate-Set (version: 3)

Iterate over a set.

Comparing performance of: for of: few items vs for of: many items vs convert to array: few items vs convert to array: many items vs native iterator: few items vs native iterator: many items vs native iterator w/ size: few items vs native iterator w/ size: many items:

Created: 5 years ago by: Registered User

Go to the latest result

for of: few items

for of: many items

convert to array: few items

convert to array: many items

native iterator: few items

native iterator: many items

native iterator w/ size: few items

native iterator w/ size: many items:

Historical Performance Data aggregated from 42 community runs

Desktop Results:

Chrome 34 runs

Firefox 8 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `for of: few items vs for of: many items vs convert to array: few items vs convert to array: many items vs native iterator: few items vs native iterator: many items vs native iterator w/ size: few items vs native iterator w/ size: many items:`